Alignment saga

[jftu105]

My daily driver was badly pulling to one side, causing sever edge wear for the front tires. Those two front tires are barely 18 months old.

I did some toe adjustments to reduce the pull but I know the camber on the right side could be quite off. Depending on the grade of the road, the car could stay straight for pull to the right side.

After replacing a flat rear tire which was quite worn and seeing also edge wear on the rear tire, I knew I need to have the alignment done professionally.

The key word is "professionally". Most the alignment shops and technicians are not properly trained. Have the car aligned in a shop does not mean it is done professionally. This is how the saga started.

Without revealing the name of the shop, here is how the story started. They first put my car up and slapped the sensors (reflectors) on all four tires. Looking from outside, I wondered how could the alignment be correct if the reflectors were not centered to the wheels. Could the alignment software (WinAlign) compensate for the centering error the reflectors, however large? The answer is NO unless the centering error is small enough.

Next thing I noticed was the technician was huffing and puffing to turn my tie-rods. I knew immediately that the guy did not release the 13 mm bolts on the tie-rods. I asked if I could go in to show them something. I was allowed. This was quite surprising because most shops would keep customers out.

I pointed out the 13 mm bolts and told the guy he needed two wrenches to loosen it. After that, he could adjust the toe much easier but the tie-rod was badly scarred by his vise grip. Then he moved to the other side (right side first). He did not loosen the 13 mm bolt again. I had to remind him again.

Finally, he got the toe right but the camber angle could not be adjusted, showing 0 degree camber. I showed him the offset bolts but the camber angle stayed the same after fairly large turn on the bolt. I told the guy that's enough, figuring that I might have to replace the offset bolts before real alignment could be done.

The car still pulled to the right side, not any better.

Two days later, after ordering four Lemforder offset bolts from FCP, I wanted to investigate why the camber angle won't change.

I got under the car and loosened the two offset bolts holding the lower control arm. The front one mainly change the camber while the rear one could also change the toe. I pushed the lower control arm as far out as possible to get the maximum negative camber I can get. I could confirm that the offset bolts are fine. The new order from FCP will be spare parts.

After that, the car was way off. The steering wheel was off and the car pulled to the right side worse than before. I am not surprised because the random camber adjustment I did.

I took the car back to the shop and asked them to check the alignment again and they would do it one more time without charges.

This time, the main alignment technician of the shop took over. He carefully put the reflectors on and checked the centering. After that, he scanned a bar code on the door and the software (WinAlign) found the car and showed pictures of where to loosen to do the alignment. I was allowed inside and under the car again. The main technician was really nice and we discussed fully for every step. He told me he just did a G-wagon a few days before.

Anyway, we first got the rear toe right. No camber adjustment for the rear tires.

We were able to adjust the camber for the front but with the offset bolt at its most outward position on the right and most inward position for the left, both camber angles are at -0.9 degree, 0.1 off the allowable range. I am happy enough. The camber range is from -0.3 to -0.8 degrees.

One interesting thing is that the software can only handle 2 degree toe adjustment. If the the toe is off more than two degrees, for example, 4.6 degrees, it would should show as 0.6 degree off. The technician told me that he has to repeat the toe adjustment by rolling the car backward and forward again and restart the software to do the alignment. The software gave out a warning sound when the toe is more than 2 degrees off, which happened in the first alignment attempt.

In the second attempt, no warning. After the software found the car, it showed that a presser bar should be installed for alignment. They don't have it so it was skipped.

Finally, we got the toe right and the camber stayed at -0.9 degree both sides. The rear showed different toe values so they were re-aligned.

Took the car out for a ride. It is finally straight. I will need to replace both front tires soon.

In conclusion, most technicians do not know how to do alignment adjustments, in particular for Mercedes. After I showed him how to do it, the technician told me that he liked the Mercedes design. I assume that he rarely sees an MB. The presser-bar, required by MB, is really not needed to get the alignment right.

All my five W124s are all now straight. If I were not allowed to go inside the shop, the job probably would not have been done with this particular shop. I am pretty sure the dealer can do it right for a cool $300. My front door neighbor just got a quote of $3000 for his BMW 528i to fix a coolant leak, tiny drop on the garage floor and topping up every few month. I could buy a very nice W124 with $3000.

jftu105

 

[jftu105]

After seeing first hand how the alignment software works, I agree that it definitely makes the job easier but also makes the technicians dumber.

Here are the steps I saw. I even got to press a few keys.

1. Drove the car to the alignment platform with the front tire just off the front rotating round plate.

2. Put the reflectors on and car in neutral, the technician rolls the car forward to land the front tires on the rotating plate. Rubber stoppers are then placed under one tire to keep the car from moving. The rotating plate probably has a shaft encoder to measure the tire rotation.

3. The technician gets in the car and turns the steering wheel, while watching the computer screen. He gets the steering straight and locks it with a device.

4. He gets off and scans the code on the door to bring up alignment information for the car.

5. He raises the car up so that he can get under the car comfortably. The alignment always starts from the rear. Right side first. He checks the computer screen which will show him the alignment procedures and pictures of the adjustment bolts.

6. For W124, the software states that the camber cannot be adjusted for the rear. This is the multi-link suspension. In one of the link, there is an offset bolt. One side is triple-square and the nut is 19 mm. Loosening the nut and with the triple-square in, he can turn the bolt and watch the computer screen until it shows green and the little marker as close to the center as possible. The fuel pump cover needs to be removed to get to the bolt. Repeat the same procedure for the left rear.

7. He then clicks a button to bring up the front alignment. The computer shows an image of a presser-bar and how to mount it. He clicks skip.

8. The screen now shows the camber, the toe, and caster angle for both sides. The marker is where the front edge of the tire. For the right tire, if the marker is to the right, it is toe out, but it is toe in for the left tire if the marker is off to the same right. It is quite intuitive.

9. He starts with the right side camber. Then the toe. The caster angle would change the toe; therefore, should be done first. No direct caster adjustment. Then, he moves to the left side to repeat the same procedure.

10. While adjusting the left side, the previously adjusted values of the right side could change. It could take a few back and forth to finally get the camber and the toe right. The caster would be whatever it is.

11. He then rolls the car back, off the rotating plate and forward again. The software is restarted. This is to ensure that the toe is not over 2 degrees off. For example, if it is 2.6 degree off, The software would consider it 0.6 degree off. After the first adjustment, the toe would become less than 2 degrees. The second alignment would show that it is, for example, 1.6 degree off. It can be fine adjusted to 0.15 degree, the middle value for the acceptable toe range.

12. The technician told me that he once had to repeat four times to get it right because someone replaced the tie-rod by himself and it was way off. Most technicians might just do it once. The alignment would be still way off.

13. Finally, with another click, the software shows the final alignment values on an image. It would be nice to be all green but sometimes, a little red, with a small error, would be fine. He can click and print a copy for the customer. From my conversation, the technician does not really know how suspension works and different types of suspensions. The software tells him where to loosen and how much he should turn.

14. Will ChatGBT and AI take over the car alignment? In a way, it already did. Many people now cannot go from A to B without GPS.

jftu105

 

[gsxr]

This story explains why I would only go to the dealer for alignments for the past few decades. Not sure what I will do now that the dealer wants $300 (!!) which I am having difficulty stomaching.

For your writeup above:

Step 3: What the tech did was wrong, but in most cases won't cause a problem. The CORRECT method is to center the steering box per the factory procedure. The steering wheel can be off one or more splines, which will result in the steering gear not being in center position when driving straight down the road. If the steering wheel is not centered, it must be removed/reinstalled in center position to match the gearbox center. On the bright side, you can check this at home without going back to the shop. The alignment should always be performed with the gearbox centered, regardless of steering wheel position.​

​

Step 7: The spreader bar is designed to simulate road forces while driving. It pushes the tires apart and takes up all play in the linkages. With all new/tight components, this is less critical. Without the spreader bar, the tech can push the tires apart by hand and see if there's any change in the toe readings.​

I always request the printout showing before & after numbers, as shown in the attachment below. There are 2 different printouts from the alignment software used by most dealerships, the one with the big red/green blocks is most useful, but the second with all the fine print has some additional data which sometimes comes in handy.

I've mentioned this before, but you can adjust front toe at home darn close to spec, using a tape measure across the tire treads front/rear. The hassle is this requires a LOT of trial-and-error adjustment. Adjusting camber, caster, or rear toe is far more difficult at home.

 

[luckymike]

Man, I really hate the whole alignment topic. In a perfect world, I'd have a rack and do my own and those of all my friends. And I DO have the spreader bar and bolt to center the gear.

 

[jftu105]

This story explains why I would only go to the dealer for alignments for the past few decades. Not sure what I will do now that the dealer wants $300 (!!) which I am having difficulty stomaching.

For your writeup above:

Step 3: What the tech did was wrong, but in most cases won't cause a problem. The CORRECT method is to center the steering box per the factory procedure. The steering wheel can be off one or more splines, which will result in the steering gear not being in center position when driving straight down the road. If the steering wheel is not centered, it must be removed/reinstalled in center position to match the gearbox center. On the bright side, you can check this at home without going back to the shop. The alignment should always be performed with the gearbox centered, regardless of steering wheel position.​

​

Step 7: The spreader bar is designed to simulate road forces while driving. It pushes the tires apart and takes up all play in the linkages. With all new/tight components, this is less critical. Without the spreader bar, the tech can push the tires apart by hand and see if there's any change in the toe readings.​

I always request the printout showing before & after numbers, as shown in the attachment below. There are 2 different printouts from the alignment software used by most dealerships, the one with the big red/green blocks is most useful, but the second with all the fine print has some additional data which sometimes comes in handy.

I've mentioned this before, but you can adjust front toe at home darn close to spec, using a tape measure across the tire treads front/rear. The hassle is this requires a LOT of trial-and-error adjustment. Adjusting camber, caster, or rear toe is far more difficult at home.

View attachment 180191

Apparently, different software packages set different alignment values. In WinAlign used by the shop, the camber is -0.3 to -0.8 degrees for the front. Yours are at -1.0 degree and are in green.

Most of the shops will not touch the gear box. The software does not indicate anything related to the gear box; therefore, the tech, guided by the software, won't do anything like that.

The spread bar and the road force simulation are not exact science. The amount of force by the spread bar (presser bar called in WinAlign) and the actual road force could be so different.

Use toe adjustment at home is not hard. I have a routine with two lines formed by fishing wires to get the toe very precisely. A hanging bob could be useful for camber but the ground needs to be flat.

jftu105

 

[jftu105]

Unfortunately, the world is far from perfect. I do not mind paying money (but not $300) to have the car properly aligned. However, I have had so many bad experience in the past from tire shops. One tech once told me that the camber was off by 0.1 degree which was why the car was pulling so hard to the right. The tech quoted $250 to replace the offset bolt. It turned out that the tire had the coning problem. I swapped the tires left and right, the car then pulled to the left. Same thing happened with another shop when one tire had some separation issue. The tech never checked the tire but went through the alignment three times to no avail. After I replaced the tire with a spare, it was straight. The first tech of this case told me that the camber could not be adjusted because I have oil leak which soaked the offset bolt.

We need to educate ourselves better so that we do not waste money to award incompetence. Now, knowing how a shop do the alignment, I have even lower confidence in them.

One final note. The second tech (the better one) told me his goal of alignment is Not causing uneven tire wear and keeping the car. Fairly good goal, I will say.

jftu105

 

[gsxr]

The alignment specs are different for different chassis. The V8 models do not have the same specs as 6-cyl, and the 034 and 036 have different specs, as does the 034 Sportline.

The tech is still wrong to not center the gearbox. Early steering boxes used a "tool" which was just a bolt with a pointy end to center the box. Later gearboxes (1990-up?) had a visual check to determine center. This is a Big Deal and also a serious flaw in the aftermarket software instructions, if they do not tell the tech to center the gearbox, NOT the steering wheel.

The spreader bar force was approved by Mercedes and the alignment specs (specifically, toe) were designed for use with the spreader. Actual driving force may be different, but that's irrelevant, the factory specs are intended for setting on the rack with a specific spread bar/force.

Factory specs at link below, sections C+D, pages 4-6:

https://www.w124performance.com/docs/mb/W124/124_alignment.pdf

 

[jftu105]

I can see the spreader bar to achieve some preloading to remove looseness in the steering components for alignment. If looseness is significant, the alignment is futile anyway. With different tires, wheels, and wheel offsets, the force would be different. If the force is irrelevant, the spreader bar is irrelevant to me as well. As long as I do not have uneven tire wear and the car is straight, I do not care about the spreader bar.

The WinAlign software offers four different models for W124 after the tech scan the code. Three of them are either with self-leveling suspension or sports suspension. I told the tech to choose the option that is neither sport nor self-leveling suspension.

In the past, I could only watch from far on how they did the alignment. This time, I got to work with the tech to go through the entire process. It gave me much better perspective on what to expect. The best outcome of this saga is that I now have a tech with a local tire shop who is now familiar with W124. I can bring my cars to him from now on. I hope he does not change jobs soon. Once he leaves, I will be in trouble again.

By the way, I visited another tire shop before going to this one. The alignment tech of this other shop told me that he had worked on MB for over 20 years. This shop charged a lot more for the alignment. The tech told me that he would sprayed the offset bolts with some liquid wrench overnight before he would work on the car. He pointed at the bolts in the rear that he would spray. However, he pointed at the wrong bolts. The offset bolts are not at the rear lower control arm because no camber adjustment, but one of the multi-links.

jftu105

 

[Jlaa]

Man, I really hate the whole alignment topic. In a perfect world, I'd have a rack and do my own and those of all my friends. And I DO have the spreader bar and bolt to center the gear.

@luckymike, I cannot remember if we chatted about this before ----- but, we live close by. We are fortunate to live in close proximity with "Custom Alignment" in Mountain View which is an alignment shop the specializes in alignments and does lots of alignments for race cars as well. It helps that they are co-located in a building with "Modderman Porsche" that services a lot of classic air cooled Porsche 356 and 911s and that Modderman sends all their cars over to Custom Alignment (all of 20 feet) for alignment as well.

As well - lots of Porsche Club club-racers have their race cars aligned at Custom.

Just take your MBs to Custom Alignment and they will align it with software and lasers but they add the step that no one else seems to do these days (because it adds so much time) --- they road test your car 3x and make fine adjustments each time AFTER the computer says its okay because they want to make sure everything is OK.

I've had my w124 and my w210 aligned by them.

 

[jftu105]

Road tests are truly the ultimate alignment step. The roads have a grade for water drainage. The grade change the camber of the tire with respect to the road surface. The inside lane typically tills down to the left while the outside lane to the right. The alignment measurements should be considered as the starting point only, assuming that the reflectors are installed correctly for correct measurements. An experienced alignment specialist can then fine tune the alignment for different road conditions. I will assume that a race car alignment will be different due to the bank angle of the race track.

Once you have sumo wrestler sitting inside your car, the camber will change as well.

jftu105

 

[luckymike]

@luckymike, I cannot remember if we chatted about this before ----- but, we live close by. We are fortunate to live in close proximity with "Custom Alignment" in Mountain View which is an alignment shop the specializes in alignments and does lots of alignments for race cars as well. It helps that they are co-located in a building with "Modderman Porsche" that services a lot of classic air cooled Porsche 356 and 911s and that Modderman sends all their cars over to Custom Alignment (all of 20 feet) for alignment as well.

As well - lots of Porsche Club club-racers have their race cars aligned at Custom.

Just take your MBs to Custom Alignment and they will align it with software and lasers but they add the step that no one else seems to do these days (because it adds so much time) --- they road test your car 3x and make fine adjustments each time AFTER the computer says its okay because they want to make sure everything is OK.

I've had my w124 and my w210 aligned by them.

@Jlaa We have discussed this. I keep meaning to ask them if they use the spreader bar and whether they lock the gear for toe adjustment. If not, I'd pay extra if they would add those steps.

Do you have a contact name or do they know you well enough that you could make that request?

 

[Jlaa]

@Jlaa We have discussed this. I keep meaning to ask them if they use the spreader bar and whether they lock the gear for toe adjustment. If not, I'd pay extra if they would add those steps.

Do you have a contact name or do they know you well enough that you could make that request?

Just call’em up and ask!

 

[gsxr]

FYI - the V8 boxes do not have a locking mechanism on the gearbox for center position, only a visual where 2 marks are lined up. If you can check this at home to verify the steering wheel is centered when the box is centered, then it's OK for the tech to center and lock the steering wheel (then double-check visually at the box before adjusting anything).




From FSM job 46-3400:

 

[Seangbadee]

@luckymike, I cannot remember if we chatted about this before ----- but, we live close by. We are fortunate to live in close proximity with "Custom Alignment" in Mountain View which is an alignment shop the specializes in alignments and does lots of alignments for race cars as well. It helps that they are co-located in a building with "Modderman Porsche" that services a lot of classic air cooled Porsche 356 and 911s and that Modderman sends all their cars over to Custom Alignment (all of 20 feet) for alignment as well.

As well - lots of Porsche Club club-racers have their race cars aligned at Custom.

Just take your MBs to Custom Alignment and they will align it with software and lasers but they add the step that no one else seems to do these days (because it adds so much time) --- they road test your car 3x and make fine adjustments each time AFTER the computer says its okay because they want to make sure everything is OK.

I've had my w124 and my w210 aligned by them.

I took my 95 E320 to MB Fayetteville and never had an issue since then with my alignment.
Once you have a dealer or shop that does the alignment per factory specifications, you should be alright.

 

[jftu105]

I took time to share something I thought useful. If you hate my posts, stop without going further. If I post something obvious, that's me, not surprising. With the above disclaimer, I would like to share a few more things about alignment.

1. Be alert and pay attention to how the car steer. Is the car pulling to one side when you let go the steering wheel briefly? Some people could be so ignorant that he or she never realizes the car is pulling to one side, even badly.

2. When the car is pulling one side quite badly, stop and park the car some where safe. One most likely scenario is a flat tire. Walk around the car and check all four tires. Do not assume any specific tires. Check all four tires for low pressure. Use a gage if needed. Typically, a flat tire on the right will make the car pull to the right and vice versa. Do this before the tire goes completely flat which would damage the tire.

3. If the tire pressures are fine. Look from the front, check the tire shape. It should be nice and square, cylindrical. Tire separation could cause the car to not align and severe vibration.

4. If the tires look fine. Swap the front tires left to right to see if the car now pulls to the opposite direction. If so, the tire might be in cone shape, causing the car to pull one side. Nake eyes cannot tell if a tire is coning or not. Move the tire to the rear to see if the alignment is fine now.

5. Check the tire wear if the car is pulling to one side. Outside edge wear typically indicates too much toe in or not enough negative camber angle. If both tires have outside edge wear, it is most likely too much toe in. If only one side has outside edge wear, it is likely camber. Too much toe out could cause inside edge wear, I think.

6. With significant tire wear, the suspension should be checked. Check if the ball joints of the lower control arm and tierods are tight and no tore rubber boots. Check the strut mounts as well. Sometimes, the looseness could be due to the loose or cracked strut mounts. Also check shocks.

7. If all are good in Steps 1-6, alignment might be needed. Now, read my first and second posts of this thread to proceed with the alignment with a shop if you could not do it yourself.

Feel free to chip in or correct me.

jftu105

 

[gsxr]

... I would like to share a few more things about alignment.

Feel free to chip i nor correct me.

This is all excellent info. The alignment can be perfect, but if the tires have abnormal wear or other flaws, this can result in pulling to one side or other issues. If you have a spare set of tires available, it can be helpful to swap tires and see if the problem changes at all.

Once the alignment is correct, the alignment should remain in spec for a VERY long time. Alignment shouldn't be needed on a regular basis after X miles.

 

[luckymike]

Just got off the phone with Custom Alignment.

For our 1989 560SEC, I was quoted $180/axle for a total of $360. When I told him the rear did not have a provision for adjustment, he put me on hold. When he got back, he said if it was a shim car, it would be $400 which covers two hours of their time. I told him it was not a shim car (the old days, shims between the control arms and frame). He then repeated that it would be $180 per axle and we started over. I eventually admitted it was unclear to me what the cost would be and the final answer was that I would need to bring the car in for inspection, then they could tell me the cost.

They do not use the Mercedes-required spreader bar for setting the toe because "their machine tells them what to do". Not real confidence-inspiring for me.

I like that they are willing to test drive the car until they are satisfied the alignment is "correct". But in my opinion this is only confirming the car goes straight and/or that the steering wheel is centered, not that the wheels are properly aligned. And whether the wheels are properly aligned will only show itself over time via tire wear. So you don't know for a while if the alignment is actually correct.

Still looking for a shop that either has and uses their own Mercedes-required toe-setting tools, or is willing to use mine to complete the alignment as specified by the factory.

 

[gerryvz]

Contact the most reputable independent Benz shops in your area (who work on older cars), and find out who they use (often these shops farm out alignment work to knowledgeable alignment shops).

Given you are on the peninsula, I'd probably call Roy Spencer in Burlingame, and find out who he farms out his alignment work to.

 

[gsxr]

Mike, as discussed earlier in this thread, the spreader bar is not absolutely necessary with all tight components. But it is nice when the shop at least acknowledges the existence of the spreader bar, and nicer when they have one and are willing to use it.

The rear has adjustment for toe only via eccentric bolts, assuming you have stock rear suspension. $180 seems like a lot for the rear only. @Jlaa, did they charge you $360 total for each of your cars?

 

[luckymike]

Dave,

I agree the spreader bar is not absolutely necessary with all tight components. I just wonder how long 'tight' lasts and am quite sure our three dailys, while not grossly loose, would not qualify as 'tight'.

I'll bet even with all new front end components, one could still introduce additional toe out while the car is on the rack by simply pushing outward on the tires. I think the angle at the inner tie rod to center link joint inherently permits this movement. My assumption is that MB was intending to compensate for this movement when new and perhaps for follow up alignments during the car's life

 

[Jlaa]

Mike, as discussed earlier in this thread, the spreader bar is not absolutely necessary with all tight components. But it is nice when the shop at least acknowledges the existence of the spreader bar, and nicer when they have one and are willing to use it.

The rear has adjustment for toe only via eccentric bolts, assuming you have stock rear suspension. $180 seems like a lot for the rear only. @Jlaa, did they charge you $360 total for each of your cars?

Hi @gsxr, they charged me $150 in 2022 to align the front of my 500E, but not the rear, because they measured the rear and determined that it was all in-spec. As well, things were cheaper in 2022.

In 2023, they charged me $180 x 2 to align the front AND the rear of my w210 because both front and rear were out of spec. The below printout is for the w210. I like how they could have just cranked the rear left toe down by 1/32" to get the rear in spec, BUT they actually took the time to make it symmetrical.

BTW - this is Silicon Valley - EVERYTHING is expensive.

 

[jftu105]

Just for the sake of discussion, I would put in some of my thoughts on the spreader bar. When a spreader bar is placed in between the front two tires, it applies a unspecified force to force the tires to open, depending on how tight it is placed. I do not believe there is any precise control of the force. If you use a tire which wider or a different wheel, the spreader may not be doing what MB originally intended.

If the tires actual opens up more by the spreader bar, it means it is more toe out. To get the tires to have same toe in as specified, more toe in adjustment will be needed. The spreader bar will press into the side wall of the rubber. Once the spreader is removed, will the tires close back in? If so, the toe in will be higher than the one without using the spreader. The spreader bar will also establish a coupling between both tires during alignment. This means when you move the tire in on the right, you will be applying a force to push the tire out on the left side. Without the spreader bar, the tires are independent from each other. The spreader bar definitely will increase the work of the alignment.

Therefore, with the spreader bar, the toe in could be higher than the allowed range. Because the alignment guy always tries to get the alignment value at the middle of the range, with the spread bar removed, the toe in will be larger. In theory, this is what the spreader bar intended to achieve because it assumes that there will be some force to open the tires during driving similar to the the spreader bar.

However, if if the toe in is higher due to the use of he spreader bar, the force during driving will be more inward to push for more toe in, contrary to the assumption for the need of the spreader bar.

In conclusion, a spreader bar is not a necessary condition for a proper alignment, which means that we cannot say:

No spreader bar, no proper alignment.

The actual driving is the ultimate alignment yardstick. The decision of Custom Align to drop the spreader bar is perfectly fine because they test drive carefully. Some engineers at MB decided the merit of a spreader bar some years ago but this hypothesis of spreader bar is not a proven science and not a physical law set in stone.

jftu105

 

[gsxr]

I believe the Beissbarth spreader bar (the mfr of the MB tool) is spring-loaded, so it applies a specific force against the wheels (i.e., whatever the spring rate is). However, I've never personally use one so I'm not certain about this. The Beissbarth website is pretty useless, there are no specifications or even a description:

BEISSBARTH: Toe press bar for Mercedes Benz

www.beissbarth.com

For reference, here is the FSM procedure for setting toe, which notes the spreader bar installation and also gearbox centering:

https://www.500eboard.co/forums/misc/Manuals/Servicev3.2/W124/w124CD2/Program/Chassis/40-0323.pdf

 

[Jlaa]

Fwiw - I messed around with the spreader bar at my independent’s shop at his own alignment rack in 2021 and it was tough. If you even touched the spreader bar, the toe value would change a little bit (a couple of minutes). And, depending if you put the spreader bar on the center of the tire sidewall, or nearer the tread, or nearer the wheel flange, you would get changing toe values… again on the order of minutes. If the bar was not completely orthogonal to the longitudinal axis of the car - again differing values. If the bar was placed at bottom dead center of the tires vs 1/2” up the circumference - again changing values. If the bar fell off and you put it back on again - diff values. So to @jtfu105 ‘s point, I kinda deprioritized the value of the spreader bar over real world driving after that.

The proof was kind of in the pudding - my independent used the spreader bar but never did 3x roadtests each time and the car always felt a little off —- always had to hold the steering wheel just a bit off….. and that was even with my independent using the other bar that holds the steering wheel in place.

Custom alignment didn’t use a spreader bar but always does 3x road tests (which actually consumes a ton of time because this is 3 more times up and down the lift after the road tests) and I have been satisfied.

I cannot say that this is EXACTLY what the FSM prescribes, but so far it has worked for me.

 

[jftu105]

Fwiw - I messed around with the spreader bar at my independent’s shop at his own alignment rack in 2021 and it was tough. If you even touched the spreader bar, the toe value would change a little bit (a couple of minutes). And, depending if you put the spreader bar on the center of the tire sidewall, or nearer the tread, or nearer the wheel flange, you would get changing toe values… again on the order of minutes. If the bar was not completely orthogonal to the longitudinal axis of the car - again differing values. If the bar was place at bottom dead center of the tires vs 1/2” up the circumference - again changing values. If the bar fell off and you put it back on again - diff values. So to @jtfu105 ‘s point, I kinda deprioritized the value of the spreader bar over real world driving after that.

Wow! Glad to know the hands on experience with the spreader bar. The instruction manual provided by Dave essentially shows a straight bar placed in between the tires, no adjustment what so ever for the force. It eventually affects minutes, not degrees. In other words, you can simply toe in a few more minutes to compensate for the lack of spreader bar if you want to. Note that one minute is 1/60 of a degree, or less than 0.02 degree. It is not exact science.

MB engineers went through the same engineering schools. They made mistakes as well. Many bad mistakes were made for W124, such as head gasket, plastic insulation of engineer harness, placing MAF over the exhaust pipe, etc. The spreader bar is one of the things which belongs in the camp of over-engineering, in my opinion.

My cheap tire shop charging at less than 1/3 of what Custom Alignment will charge delivered a straight running car for me without the use of the spreader bar. I am happy and my wallet is happy. End of story.

The value of posting a thread on 500e is that I have learned more from what I have contributed. I cannot say the same thing about my experience when I posted on BZworld. SBxxx will be cursing at me along with so many so called purists, simply because I did not follow exactly what MB stated.

jftu105

 

[luckymike]

Just to get it on the record, per the W126 manual, 40-320, page 964, wheels should be pried apart with 90-110N. My spreader bar is set up to provide this. I was going to apply this to our W124 failing any other resource.

Very good info from @Jlaa about how varied the numbers are when moving the spreader bar around.

 

[TerryA]

Just got off the phone with Custom Alignment.

For our 1989 560SEC, I was quoted $180/axle for a total of $360. When I told him the rear did not have a provision for adjustment, he put me on hold. When he got back, he said if it was a shim car, it would be $400 which covers two hours of their time. I told him it was not a shim car (the old days, shims between the control arms and frame). He then repeated that it would be $180 per axle and we started over. I eventually admitted it was unclear to me what the cost would be and the final answer was that I would need to bring the car in for inspection, then they could tell me the cost.

They do not use the Mercedes-required spreader bar for setting the toe because "their machine tells them what to do". Not real confidence-inspiring for me.

I like that they are willing to test drive the car until they are satisfied the alignment is "correct". But in my opinion this is only confirming the car goes straight and/or that the steering wheel is centered, not that the wheels are properly aligned. And whether the wheels are properly aligned will only show itself over time via tire wear. So you don't know for a while if the alignment is actually correct.

Still looking for a shop that either has and uses their own Mercedes-required toe-setting tools, or is willing to use mine to complete the alignment as specified by the factory.

@luckymike,
Mike,
I know of an excellent alignment shop in Costa Mesa. They did my 500E a long time ago. I have no weird wearing tires. I can’t find the name of the company at the moment. It’s been a while since I’ve been there but the guy doing the alignment was very familiar with Mercedes cars. He may or may not still be there. If you’re interested I could check them out for you.

 

[jftu105]

Just received four offset bolts from FCP. Lemforder, made in Italy, for $11-12 each and free shipping. Part # A201330 0018. Not a bad deal at all, but they are not needed for now. A Ferbi actually costs more. On the bag, it also states: aftermarket.zf.com.


Will probably replace all the offset bolts if I am going to do alignment for any of my cars. In that way, I can shut up the tech if he states "your offset bolt is worn."

jftu105

 

[luckymike]

@luckymike,
Mike,
I know of an excellent alignment shop in Costa Mesa. They did my 500E a long time ago. I have no weird wearing tires. I can’t find the name of the company at the moment. It’s been a while since I’ve been there but the guy doing the alignment was very familiar with Mercedes cars. He may or may not still be there. If you’re interested I could check them out for you.

@TerryA Terry, we've lost our Newport Beach connection so we probably won't be down there again for quite some time. Thanks, anyway!

 

[TerryA]

@TerryA Terry, we've lost our Newport Beach connection so we probably won't be down there again for quite some time. Thanks, anyway!

@luckymike,
Sorry to hear that. It was nice while it lasted.

 

[jftu105]

I believe the Beissbarth spreader bar (the mfr of the MB tool) is spring-loaded, so it applies a specific force against the wheels (i.e., whatever the spring rate is). However, I've never personally use one so I'm not certain about this. The Beissbarth website is pretty useless, there are no specifications or even a description:

BEISSBARTH: Toe press bar for Mercedes Benz

www.beissbarth.com

For reference, here is the FSM procedure for setting toe, which notes the spreader bar installation and also gearbox centering:

https://www.500eboard.co/forums/misc/Manuals/Servicev3.2/W124/w124CD2/Program/Chassis/40-0323.pdf

A spring loaded spreader bar is definitely more consistent in applying a constant force, depending on how much the bar is compressed. Once the large compression is set, small variations do not change the force too much. Simply Hooke's spring law. Spring loaded design is used in my applications from the belt tensioner, belt saw, to high speed machine tool spindles.

For that being said, I am still not convinced by the merit of the spreader bar. First, if there is substantial looseness in the steering chain, alignment is moot. Spreader bar actually would mask the problem, similar to taking some drug to lower the blood pressure. Second, with most front tires arranged to be toe in, the steering force acting on the front tires are pushing in, not spreading out as the spreader bar. The steering side force is proportional to the slip angle (or the toe in angle when the car is going straight). The use of a spreader bar will actually increase the toe in angle than the one without, based on my analysis. As a result, there are more force pushing the front tires in, totally different from the force the spreader bar tries to simulate.

Let those who believes in the spreader bar to exercise their belief. For me, it is a NON-issue, definitely not a necessary condition for proper alignment, neither is it a sufficient condition. My car is straight without it.

jftu105

 

[jftu105]

Less than a week after I received the offset bolts, I got this email from FCP. Should I get another set?

 

[luckymike]

Yes.

On second thought, they're only $10 at the dealer:

 

[gerryvz]

Yes, I would always go MB OE for important parts like this.

 

[jftu105]

So, I paid over $11 each at FCP while the dealer only charges $10. it is Lemforder, not any lousy ones. And then after a week, it was discounted to $8.00 after I bought it, four of them. $12 in loss?!!!! I will go bankrupted at this rate.

jftu105

 

[gerryvz]

I will go bankrupted at this rate.

jftu105

You should invest $20,000 in the "E500E Micro-Mileage Preservation Private Equity Fund" we are putting together. That will make you money over time.

 

[sheward]

I hereby volunteer to manage the assets!

 

[jftu105]

I hereby volunteer to manage the assets!

That's very shrewd.

jftu105

 

[jftu105]

When the alignment is bad, it leads to edge wear. At what point, the edge wear becomes dangerous? My front two tires are still quite good with deep thread but the edge wear is substantial. Should I replace them? I guess a picture is needed.

jftu105