Transmission Modifications, Gearbox and Differential Ratio

[Jim]

I start a new thread so as not to Thread Jack 500 DXB's Oil Pressure Thread.

...Muscat...cooler weather. Quick question the 722.370 Gearbox, 2.65 Differential you have would you recommend them? Also you ever get the AMG back muffler sold? cheers

Just this week it is getting cooler. Tonight tor the first time in 6 months I came in from my walk/run without being completely drenched in perspiration.

The 722.370 is performing well the only thing I notice is, if I start in 1st the 2-3 shift is very soon after the 1-2 shift...but I am still playing.

I love the 2.65 and am looking for 2.24 from a USA E420. I can notice the higher ratio at low speeds. At higher speeds if I do not get what I want the gearbox shifts down an off we go.

So yes great gearbox and the diff. ratio depends upon your driving requirements. Relaxed cruise vs. tyre shredding launch.

I still have the AMG rear box.

 

[500 DXB]

Interesting what sort of costs would a 2.24 be approx? Recommended? My car has 136k on it so hoping plenty of miles left in the box so far, also had the gear box mounts done last year by previous owner, cheers

 

[gsxr]

The 2.24 diff should be easily available in the USA, pretty cheap too... just make sure the donor is from a 400E/E420 (124.034) with ASR!! However shipping the diff overseas (approx 100 lbs / 45kg) would cost a small fortune. It would require a full-time first-gear start, and be a bit slower on takeoff; but should improve freeway fuel economy.

Top speed should increase a bit to ~170mph/270kph, the exact top speed is unknown but is limited by the 5.0L power output. The usual claim is 170-175mph with a mostly-stock 5.0L motor and otherwise stock .036 (i.e., no fat wheels to reduce the cD and possibly reduce top speed). Now a 6.0L with 2.24 gears should crack 180mph/290kph, maybe a bit more, if you can find enough road and cajones....

 

[Trae]

Dave,
If and when my transmission gives up (I have a new transmission with 30k on it), would it be feasible to join a 2.24 from a 400E/E420? I had a 400E that got 24mpg. vs. the 20mpg. I now get with my 2.82 on the 1993 500E.


Trae

 

[gerryvz]

I think it's going to be the rear-end (pumpkin) differential that you'd want to swap to change to the taller gearset, not the transmission (gearbox) itself. And with only 30K on your tranny, it's going to be pretty much before hell freezes over (in terms of time) before it gives up the ghost.

That said, a change is not going to give you much better MPG - perhaps 1 MPG better than you are getting now. The real improvements are with the engine itself, based on displacement and power generation.

I modded my 560SEC's 2.47 to a 3.07 gearset. Over approximately 55,000 miles, I have lost a whole 1 MPG with the modified rear end, but gained a heck of a lot of low-end acceleration. Only problem is when it's wet out -- rear wants to break loose all the time, and the SEC has no traction control nanny like the E500E does.... I have probably lost 5-7 MPH at the top end, but seeing as I never get up above 100 MPH that often, it's no big loss.

Cheers,
Gerry

 

[gsxr]

Gerry is correct... you can swap the rear end (differential) to get different gearing. No need to mess with the tranny.

The 500E stock gearing is 2.82 which is the best compromise for acceleration, fuel economy, and top speed. This of course can be changed to accommodate specific needs. For a slight change, you could install 2.65 gears, although as noted above there may only be about 1mpg difference, maybe. If you do a lot of freeway driving, or have a long commute at freeway speeds (or at least not city stop & go), then the 2.24 gears might provide a decent increase in fuel economy, but still likely to be in the 2mpg range (i.e., bumping your 20mpg up to 22 or so, maybe).

The 1993-95 400E/E420 gets surprisingly good mileage due to the tall 2.24 gears, and also due to the higher 11:1 compression ratio. The 1992 400E had a 10:1 compression ratio and slightly lower fuel economy. Assuming you had owned 1993 400E, you can figure that with the same gears but a larger motor (and at lower compression), 22mpg would be pretty realistic. Another option would be to get a 400E/E420 as a commuter car rather than rack up the miles on the 500, if fuel economy is a concern. Or even - dare I say it - an MB diesel!! {flame suit on}

 

[szvook]

dare I say it - an MB diesel!! {flame suit on}

 

[400Eric]

I've been saying for years (Stevo will back me on this) that EVERY 500E owner should have a 400E/E420 as a daily driver commuter car. Save that 500E for the weekends! Nice 034s can be had for much less dough than W124 diesels too!
Regards, Eric

 

[Trae]

Thanks guys,
I had a pristine 93' 400E until a truck T-boned me and totaled it. The 500E is a lot more fun to drive. I have been brainstorming over the fuel mileage, but the difference is so small that I think I'll stick with the current fleet.
If I do anything, it would be to buy Dave's E420, but the wife does NOT agree with yet another car.:sorrow:

Trae

1992 500E Renntech
1993 500E Daily driver
1994 E320 wagon-wife
2001 Sl500 Special occasion

 

[jhodg5ck]

IMHO, going 2.24 is the way to go w/ a street 500E, I plan on doing as much when I finally get a proper example..;-) My Hammer wagon came with a 3.27 in the rear and it was retarded in every way imaginable. 60mph @ 3000 rpm..FML. Dropped in a 2.24 LSD gearset out of a wrecked 500SEC w/ less the 2K on the clock. Life is Grand now..last Long trip I netted 19 mpg, and that was cruising 80-100, with a few 135-145 romps along the way over about 500 miles.

For me @ least, how often are you launching the car from a stand still..around here, no one ever wants to race, it sucks...BUT, I do find people who want to play on the highway from time to time..

With the 2.24 you are good for about 90 odd IIRC in 2nd and about 130 in 3rd, they're good gears for playing Dropping 4th is just like having a 722.6, much win.

I suppose it also depends what your typical cruise speed is...down here, you can get away with 80-90 Easy, roll about 100 when things Open up and you can see. Make good time! Last trip home, 500 miles in just a nick over 6 hours w/ a stop for fuel.

jono

 

[gsxr]

Jono has a good point. If you spend a lot of time in the city from stoplight to stoplight, gears in the 3.06-3.27 range might be more fun. If you spend more time on the freeway at 75-90mph, the taller 2.24-2.65 gears can make more sense. Totally depends on your intended usage... of course the ideal would be a 722.6 which allows the best of both worlds, but alas, there is no simple swap for our old iron.

 

[Alpina]

I had a 2.65 ratio on my 500E .. and the car was delimited,, so i saw often over 280+ on the speedo (( 300 km AMG instrument)) but the main reason for swapping 2.65 vs 2.82 was just to get the rpm down at traveling speed.. maby the car was not as fast off the line ,, but quick enough

 

[400Eric]

IMHO, going 2.24 is the way to go w/ a street 500E, I plan on doing as much when I finally get a proper example..;-) My Hammer wagon came with a 3.27 in the rear and it was retarded in every way imaginable. 60mph @ 3000 rpm..FML. Dropped in a 2.24 LSD gearset out of a wrecked 500SEC w/ less the 2K on the clock. Life is Grand now..last Long trip I netted 19 mpg, and that was cruising 80-100, with a few 135-145 romps along the way over about 500 miles.

For me @ least, how often are you launching the car from a stand still..around here, no one ever wants to race, it sucks...BUT, I do find people who want to play on the highway from time to time..

With the 2.24 you are good for about 90 odd IIRC in 2nd and about 130 in 3rd, they're good gears for playing Dropping 4th is just like having a 722.6, much win.

I suppose it also depends what your typical cruise speed is...down here, you can get away with 80-90 Easy, roll about 100 when things Open up and you can see. Make good time! Last trip home, 500 miles in just a nick over 6 hours w/ a stop for fuel.

jono

X2! There is nothing like being able to drop all the way down into first gear when entering a freeway onramp where there's almost always some yahoo in the other lane who thinks he's going to get his beastly truck to that part where the two lanes neck down into one lane before that old Benz does! There is nothing better than shoving it up the ass of someone who is trying to shove it up yours!

It's also major fun to be able to drop all the way back down into second while doing 70 MPH! That makes you pretty unbeatable in the freeway wars.

Dave, how come when I sing the praises of 2.24s you razz me pretty hard but when Jono does it you say he "has a good point"? I know that Jono has some pretty impressive credentials but let's don't forget who has the quickest naturally aspirated 2.24 geared 4.2 powered W124 in the universe! That counts for something too!

Jono, was that wrecked 500SEC w/ less than 2K on the clock that provided you that 2.24 LSD gearset a US market car? How did you manage to score that gearset? Did the whole pumpkin bolt in or did you have to swap in just the gearset?
Regards, Eric

 

[gsxr]

Dave, how come when I sing the praises of 2.24s you razz me pretty hard but when Jono does it you say he "has a good point"? I know that Jono has some pretty impressive credentials but let's don't forget who has the quickest naturally aspirated 2.24 geared 4.2 powered W124 in the universe! That counts for something too!

Because, Eric, you are in search of every possible tenth (or hundredth) of a second at the dragstrip, while still running 2.24's... when dropping to 2.65/2.82 would net you a couple of tenths and maybe make history as the first 13-second 400E with a stock motor (assuming traction is available). The 2.24's are nice on the freeway but I'm not as crazy about them around town. That's why the 722.6 is the holy grail, it allows you to have your cake and eat it too.

Jono's point was that gearing selection depends on your usage & driving habits; however you have a somewhat blind love for tall gears. I'm surprised you haven't looked into getting custom R&P's in the 1.75 range as the 2.24's may not be tall enough for ya! LOL! Ah, running through the 1/4 mile in 2 gears... making your 722.3 into a Powerglide...

 

[400Eric]

LOL, you know how much I hate Chevies.

I know I also mentioned at some point that I love how I am able to zip through downtown, bobbing and weaving, zigging and zagging, working through that traffic, all without ever shifting out of first gear! And the beauty of it is that I'm not even stressing the engine since it's not over-revving until we get past 50 MPH! So to me that makes the 2.24s ideal for around town use as well!

Yes, a 722.6 would indeed be the holy grail, and it's one of the reasons why I fantasized openly about owning a M119 powered W210 on the old site, only to have you and EVERYBODY else (but Glen) shoot me down for even thinking such blasphemy. I have to continually bring this up because you still haven't thanked me for turning you on to them!
Regards, Eric

 

[gsxr]

I know I also mentioned at some point that I love how I am able to zip through downtown, bobbing and weaving, zigging and zagging, working through that traffic, all without ever shifting out of first gear! And the beauty of it is that I'm not even stressing the engine since it's not over-revving until we get past 50 MPH! So to me that makes the 2.24s ideal for around town use as well!

This is a crackup. You're the same guy that wanted 2.24's to keep the revs down, to make the engine last longer! But now you're winding it up in 1st gear around town instead of keeping the revs at 700rpm? I'm so confused.
:fish:

Yes, a 722.6 would indeed be the holy grail, and it's one of the reasons why I fantasized openly about owning a M119 powered W210 on the old site, only to have you and EVERYBODY else (but Glen) shoot me down for even thinking such blasphemy.

I have no recollection of said shooting down, but I'm still not a fan of the W210. I am definitely a fan of the M119, 722.6, and M119+722.6 combo, but that is just the powertrain, not the chassis.

I have to continually bring this up because you still haven't thanked me for turning you on to them!

Bah! If anything, I BLAME you! LOL! The 210 is no 124, that's for sure. I'd like to try an '02 E55 for grins someday. Shame they never imported the W210 E60, there was just the one black E60 in the USA, and that white one in Canada. The E55 doesn't have quite enough of a power advantage over the 500E (and besides, it's a *spit* M113). The 6.0 has the power but they hardly built any of those at all - bummer. (They don't even appear in the EPC!)

 

[400Eric]

Jono, was that wrecked 500SEC w/ less than 2K on the clock that provided you that 2.24 LSD gearset a US market car? How did you manage to score that gearset? Did the whole pumpkin bolt in or did you have to swap in just the gearset?
Regards, Eric

Re-posting this question again as it is definitely on topic and of interest to the OP as he did state in his first post that he wants 2.24s. Jono, please do tell!
Regards, Eric

 

[jhodg5ck]

Oooo...look what I missed...ah, you's guys...

anywho.. the beauty of a Hammer is the custom rear subframe was built with the sole purpose of housing an S class differential. The 500SEC diff I acquired came from a Euro spec 84 that made friends w/ a tree far too early in her life...I did however also acquire a number of Gorgeous SEC parts in the process of getting this diff, but that's another story..actually, the front seats are still available in anyone has interest..

That said, I'd wager the R&P/LSD from this Gen I 126 diff could be mated to a 124, but for me, I'd take the oppertunity to built a Quaife were I in any situation then the one described here.



Ya'll play nice:-D

J

 

[400Eric]

Thanks Jono.

Dave says that the Quaife is not a option for 2.24 or 2.47 gears. That's why some of us are looking for other options.

Some folks mistake the free exchange of different ideas and perspectives for arguing. Dave knows that we love him!
Regards, Eric

 

[gsxr]

Jono, sounds like for a Hammer, swapping in a 400E/500E subframe with 210mm diff would be an easy way to simplify rear-end changes (depending on the ratios desired). The 210mm diff that fits the 124's did not exist in 1986 which is why AMG had to do the hack job to fit the W126 diff.

As noted, the Quaife only works with 2.65/2.82/3.06 gearsets. For 2.24 and 2.47 you can use the factory clutch-type LSD's, but those are better suited for straight-line racing, IMO. I assume AMG had the GT diffs made for 2.24/2.47 applications but then you're back to having custom gears made to replace the ones that blow up. I also believe the AMG GT diffs are NLA... any idea who made them for AMG?

Decisions, decisions!

 

[jhodg5ck]

Well, I might consider replacing it, but the custom subframe is one of the Major parts that make a Hammer a Hammer..it's a part of the car they spent a Lot of time fabbing up, so given the rarity of it I'd be inclined to leave it be..

The GT diff's were made by Gleason/Torsen...they refuse to have anything to do with these..not only do they admit the design was flawed but also make Note of the fact AMG nearly bankrupted them...thus brining these up is met w/ some frustration on the other end of the phone..

I know where One NOS GT is..it ain't cheap either.. I'm having some small odds and ends fabbed that I need here, perhaps I'll tear down some of my GT's and see if I have a gear we can pattern off of, chat with my military industrial complex/aerospace friends and see what they have in mind.

 

[400Eric]

Well, I might consider replacing it, but the custom subframe is one of the Major parts that make a Hammer a Hammer..it's a part of the car they spent a Lot of time fabbing up, so given the rarity of it I'd be inclined to leave it be..

There would be no harm in gently removing said sub-frame and putting it on a self, and replacing it with a 400E/500E subframe with a 210mm diff. That way you could preserve the rare original piece AND have the advantages that Dave spoke of. You could always swap the original back in whenever you want.
Regards, Eric

 

[jhodg5ck]

I Suppose one could, but then again, I don't plan on tracking any of the Hammers..they're simply too rare and I don't feel like having to fix them should I or It do something untoward..! That's what the track rat is for, if it blows up..well, OK..time to build something faster..

 

[Mikemcnair]

FTLT,

quick question: is it possible to fit an SL500 Diff in a 500E? i mean, i know its possible as ive just completed it, but the diff housing is longer, making the driveshaft seem to CLUNK and WOBBLE against (i assume the center support) or SOMEWHERE under the car under load.

its a terrible noise, but at slow speed, or just "normal human" acceleration its totally fine.

any thoughts would be greatly appreciated!!

-Michael

edit: the old housing is almost a full inch shorter than the new, which my boss ordered so i assumed it was the right one, and it DID go in, and DOES run ok, but this clunking is BAD and feels like its hitting the actual chassis. i guess this all makes sense as to why it was so difficult to put in :/

 

[gsxr]

Only the 129.066 1990-1992 500SL diffs are a direct swap into a 500E.

The later 129.067, 1993-1998 500SL/SL500 use an entirely different housing, which as you discovered, does not fit.


1) Why was this done? There's no need to upgrade the stock diff in the 500E (besides making it limited-slip).

2) If the new housing is 1 inch longer, the rear driveshaft will need to be shortened 1 inch. Or just take the silly thing out of the car and put the proper diff in there.

3) The late R129 diffs do not have provision for ASR sensors in the diff, like the 500E does. What did you do about the ASR speed sensors??

 

[jhodg5ck]

you Can use early W140 diff's..they come w/ a 2.65 and all have ASR..

just need to change over the rear cover.

Jono

 

[Mikemcnair]

thank you for the swift reply!!! by your SN i see your a bike guy too, i sadly just sold my 2nd R6 (2003) and miss it dearly!

please see my answers to your Q's below in BOLD

Only the 129.066 1990-1992 500SL diffs are a direct swap into a 500E.

The later 129.067, 1993-1998 500SL/SL500 use an entirely different housing, which as you discovered, does not fit.

well, it fits, but sux at function (under strong load )


1) Why was this done? There's no need to upgrade the stock diff in the 500E (besides making it limited-slip).

long story short: my boss has 2 500Es, one that is silver, mint, and has ~40k miles on it, is never touched, and is amazing. the 2nd, which i am to acquire once its running right, is a charcoal grey (looks black) car that has 250k miles, and has had EVERYTHING replaced. (i literally have $60k in reciepts worth of preventitive maintance over the last 5 yrs, as he owns a MB/Ferrari/high end restoration shop here in PA.

anywho, the dif that was in it was making a whining noise, so he ordered another, it arived and did not have the openings for the proper sensors, so that was a bust (and is currently sitting on the floor here at the shop with a low price tag if anyone wants it lol) and then got THIS dif.

now, i have been working on cars for a LONG time (20 yrs or so) and i am NOT well versed with MB's, so, i was told "put that diff in your new car", so i did it.

while doing so, as you could imagine, it was hard to get in, and was told that is normal for these cars. so, i moved forward, buttoned her up, and drove it. felt perfect, and i was pleased.

then, HE took it out, and came back to the shop after like 30 seconds claiming there was a noise, sure enough, when under load it does indeed make a clunking/banging under the rear seats (which i can only assume is the center support getting too much stress from the drive shaft being tweaked per se)

a coworker and i then looked closely at the old and "new" fid, and sure enough, they are a goo 3/4-7/8" different in length.

at this point, i want to curl up in a ball and cry as i want this car SO badly (it really in a nice piece)

2) If the new housing is 1 inch longer, the rear driveshaft will need to be shortened 1 inch. Or just take the silly thing out of the car and put the proper diff in there.

agreed, and due to the fact that shortening the DS is more work than its worth, and will forever be improper for the car (if the dif goes again for instance) i will likely take the parts out of the bad housing and swap them with the parts from one of the good housings.

3) The late R129 diffs do not have provision for ASR sensors in the diff, like the 500E does. What did you do about the ASR speed sensors??

the sensor holes are indeed there, which was one of the reasons i believed it was proper (from a visual inspection stand point, with limited MS dif experience.

so basically, i gotta get messy and rebuild the old housing, which i am frankly NOT looking forward to, but this car is so clean, nice, and runs SO well without a single squeek, rattle, drip of fluid, etc, that i cannot pass it up. plus, we worked out a trade for 2 of my "beaters" (a '92 190E 2.6 w/ Trac, and a '00 escalade that need a TON of help) for this car as im sure he can profit from them, they are not worth much, and well, I WANT A 500E!!

 

[gsxr]

you Can use early W140 diff's..they come w/ a 2.65 and all have ASR..

just need to change over the rear cover.

Warning: only some of the 140 diffs are a bolt-in. I think the 3.2L and 4.2L, and ASR was optional on both. And, only the early models have the sensor holes in the diff, in mid-95 they moved the sensors to the rear wheel bearing area instead of the diff. And yes, the rear cover has to be swapped. The W140 5.0L and 6.0L (all years) used the larger, reinforced diffs. The early 4.2L (400SEL) with ASR is the closest bolt-in, with a cover swap.

The early R129 diff is 100% bolt-in, including the cover, but ASR was optional on those too... and it's a 2.65 ratio.

 

[gsxr]

so basically, i gotta get messy and rebuild the old housing, which i am frankly NOT looking forward to, but this car is so clean, nice, and runs SO well without a single squeek, rattle, drip of fluid, etc, that i cannot pass it up. plus, we worked out a trade for 2 of my "beaters" (a '92 190E 2.6 w/ Trac, and a '00 escalade that need a TON of help) for this car as im sure he can profit from them, they are not worth much, and well, I WANT A 500E!!

OK. I'm still not clear what diff you actually installed, that had the sensor holes. What year/model did it come from?

At any rate, all you need to do is remove the wrong diff, and install the right diff. And then see what damage you may have done to the center support on the driveshaft, as it's quite likely something bad happened up there. To R&R the diff you are supposed to loosen the two bolts for the driveshaft support, this will allow the rear driveshaft to move forward a few inches and let the diff come out easily. If you had trouble installing the diff... that was the first red flag.

Anyway, used 500E diffs are not that hard to locate. They almost never go bad so IMO, it's not worth the trouble of attempting to rebuild your old one. Just install a used one and drive the car. Here's a cheap one on eBay right now:
http://www.ebay.com/itm/251096152126

You can also use a 1992-1994 400SEL / S420 diff but only if the donor has ASR (otherwise it won't have the sensor holes), and you'll need to swap the rear cover. The early R129 diff has a taller gear ratio so although it a straight bolt-in, you'd need an electronic speedo correction box.

If the driveshaft is damaged, any 400E driveshaft will work as a replacement. Here's one for sale, but you could probably find one cheaper, as there isn't much demand for these:
http://www.ebay.com/itm/200789172785


Sounds like a good deal on your "new" 500E, btw... swap that diff and start driving it!!

 

[jhodg5ck]

Hrrmm..I used one from a Gen I W140 500SEC/S500 Coupe 2.65, dropped right in w/ the cover swap NP!

 

[samiam44]

Dave,

I though the 420sel was a 2.82 ratio- the 5.0 liter's were 2.65, SL or S-class.

 

[gsxr]

Dave, I though the 420sel was a 2.82 ratio- the 5.0 liter's were 2.65, SL or S-class.

Correct.

 

[Taxi Driver]

you Can use early W140 diff's..they come w/ a 2.65 and all have ASR..

just need to change over the rear cover.

Jono

Hi, not really all, found this at one breakers yard, from a '93 500SEC, says, 2.65 non ASR!? WDB1400701A147100
odd imo,,Roger

 

[gsxr]

The W140 5.0/6.0 cars used a larger housing with reinforced diff and 1.4L fluid capacity. It's possible that early ones (1992-94) may have had ASR sensor holes and been close enough in size to fit in the 500E, since Jono says he got one to fit, but I've never personally tried. I don't think I'd want the extra weight, and there's no way to make the reinforced diff into an LSD. There are plenty of donors available with the correct housing if you need to swap diffs...

 

[jhodg5ck]

Non ASR S class..interesting, Really don't see that state side!

The one we did got one of those phantom grip/kleemann style LSD's, good for straight line stuff..

jono

 

[Mikemcnair]

Hey guys, thanks for all the help!

Heres the whole story:

My boss owns 2 500Es, one I just acquired (as stated) and he said it needed a diff, he had the "replacement" ready and I tried to install it (mind u, been working on cars for 20 yrs, but am a total MB noob, please keep that in mind through this message!)

So, I struggled, it failed cause it was wrong, I pulled it, took the STOCK housing and a known GOOD diff from a housing W/O the holes for te sensors (also a 2.82 so the guts were an easy swap) and plopped it in.

Bam!!! Car WAS perfect, for like 20 miles. Then, howling and noises and badness.


Why? Pinion seal was shot!! So, it was pissing all fluid out on decel. During accel; perfect! Cars great!

So, with fluid, perfect, without, not perfect.

Where did said diff come from, no clue, I just did what I was told, and then realized this car was to be mine, so I reallllllly started to take it seriously, not that I don't all cars, but this is the car my son will ride in, so it MUST be perfectly safe and strong.

Anyway, I have 3 riffs now, one in car, one in parts room with bad guts but right housing (for sensors) and another that's totally wrong for the car but housing and seals are good, guts are bad.

Thats what I know basically.

Thank u all for your help and insight, I wish I knew where these riffs came from, their mileage etc. but, I know this:

When fluid is in the diff, car is happy, runs like new (better than in fact as its lightly modded, and I have $60k in receipts and a folder about an inch thick of allllllll the receipts for YEARS. Which is good.

Oh, and I do have all the new seals I need, as well as the center support (whomever said it above was right, it's totally shot)

So, in the end, u will see me post here quite a bit as now an owner, and pleased to be so!

Thank u all again!

-Michael


Ok, spoke too soon. Pinion bearing blew, blowing the front seal, and making a mess.
Now, I have 2 digs here with good bearings but NO CLUE how to remove the pinion and shaft from the housing.

Ps, the digs here are numbered "ACJ 370" and "GGG40.... U92"

So basically, how do I remove the pinion so I can steal a bearing and assemble this now toasted dif?

Thanks in advance again guys!

 

[Mikemcnair]

Oh, and the housing I'm using says ACD344 on it, if that means anything

 

[gsxr]

I hate to say it, buttttttt... I wouldn't waste another penny, nor another minute, trying to fix that diff. The MB pinion depth is set using machines at the factory that literally nobody has. Blueing the gears is impractical due to the work required to R&R the pinion each time, plus a new crush sleeve is required each time. Wanna read more? Click here. He's describing a ring & pinion swap, but you are basically doing the same thing by having to R&R the original pinion. Absolutely, totally, without question, not worth the hassle. Not to mention the special tools needed to do the work (unless your shop has these, which I doubt, since most shops don't repair MB diff internals).

Just get a good used diff, complete (like this one) and drop that in. Done and done. You're in for hours more headaches if you keep trying to mess with the diff you have now. These things almost never go bad, which is why buying a used one is generally a safe bet.

Have fun!

 

[Mikemcnair]

Thanks dave, I agree, buuuttt:

I work 60 miles from home and am to commute home tomorrow to pick up my son, soooo, I need wheels

Aside from no ASR (and presumably ABS) would it kill me to drive the car with the dif that has NO holes for the wheel speed sensors?

Sounds ghetto, but it would get me home and back to work Sunday evening (I live in the town I work sun-thurs)

Obviously all the lights on the dash will be freaking etc, but that's fine with me if I can drive 100 miles or on a dif with the sensors unplugged.

As always, thank u and I look forward to your insight!

-Michael

 

[gsxr]

If the spare Frankendiff will physically bolt in, then yep, it should work... no ABS and no ASR, as you suspected. Possibly could trigger limp-home mode too but it would be driveable!

 

[Mikemcnair]

If the spare Frankendiff will physically bolt in, then yep, it should work... no ABS and no ASR, as you suspected. Possibly could trigger limp-home mode too but it would be driveable!

well said!!!

and how bad is "limp" on these cars? i may just take the 560 sec home but would reallllllllllyyyyy rather not.

i may just try the franken with no sensors, ill post back shortly.

thanks again!!!!

 

[gsxr]

The limp mode means that the first half of the throttle pedal travel doesn't do anything, so your foot is much further down than usual. And, you won't have full power available, but plenty to still drive 100mph if desired.

What, you don't like the 560SEC? Sssssshhhh, don't tell Gerry!!! LOL!!

 

[gsxr]

FYI - another 500E differential popped up for sale in the classifieds, click here.

 

[gerryvz]

What, you don't like the 560SEC? Sssssshhhh, don't tell Gerry!!! LOL!!

 

[Mikemcnair]

Dave,

Thanks for the link, I've been in contact and will have that dif ASAP! I appreciate the help!

The frankendif didn't bode well, so I had to bring an '84 380SE home, the 560 stayed at the shop.

Frankly, this car is mint. One owner (still) 93k miles, and perfect. So I don't mind it. I wish I was driving my 500 but all things happen for a reason. Soon enough I'll have her on the road again. It's just sad that since I got her I've only had 82 miles of pleasant driving.

Thank u all again for the help! I'll be on here for a long time!

-Michael

 

[mikesanto70]

Do you know is there is a 3.07 gear swap for 1997 SL500, aren't all 1972-1997 V8 benzes supposed to have a 215mm ring gear? Would love to put some gear in my SL that would REALLY wake that thing up

 

[mikesanto70]

I think it's going to be the rear-end (pumpkin) differential that you'd want to swap to change to the taller gearset, not the transmission (gearbox) itself. And with only 30K on your tranny, it's going to be pretty much before hell freezes over (in terms of time) before it gives up the ghost.

That said, a change is not going to give you much better MPG - perhaps 1 MPG better than you are getting now. The real improvements are with the engine itself, based on displacement and power generation.

I modded my 560SEC's 2.47 to a 3.07 gearset. Over approximately 55,000 miles, I have lost a whole 1 MPG with the modified rear end, but gained a heck of a lot of low-end acceleration. Only problem is when it's wet out -- rear wants to break loose all the time, and the SEC has no traction control nanny like the E500E does.... I have probably lost 5-7 MPH at the top end, but seeing as I never get up above 100 MPH that often, it's no big loss.

Cheers,
Gerry

Do you know is there is a 3.07 gear swap for 1997 SL500, aren't all 1972-1997 V8 benzes supposed to have a 215mm ring gear? Would love to put some gear in my SL that would REALLY wake that thing up

 

[gsxr]

Do you know is there is a 3.07 gear swap for 1997 SL500, aren't all 1972-1997 V8 benzes supposed to have a 215mm ring gear? Would love to put some gear in my SL that would REALLY wake that thing up

The gears changed over the years and most of the "large" gears through the early 90's were 210mm. The 215mm didn't appear until late 90's. If you have a 1997 SL500, I believe that has a 210mm "reinforced" differential. I'm not sure what other gears are available for it.

http://www.w124performance.com/docs/mb/other/diff_210mm_reinforced_35-0500.pdf

 

[d333gs]

I don't actually have a 500E but rather a 86560SL: I am curious about a gear ratio change to 3.98:1. I believe there is a stock 3.68 in there now: Reason for the desired change is that I am now in the South of France where most of the roads are curved with lots of hills and hard turns.........I spend most of the time with the car in 2nd & 3rd rather than drive .........I think I will need a euro sway bar too vs the one on this US version
Any comments or ideas?
Thanks,
John

 

[gerryvz]

3.98:1? Holy Moly -- that's extremely high !! Do you rather mean 2.98:1, which would be more in the ball-park?

A US-spec 1986 560SL is going to have a 2.47 rear-end.

It is possible to change the rear-end gearing. I have gone from the 2.47 to a 3.07 in my 1989 560SEC (same powertrain as your car) by utilising the gears from a W116 model, with a slight bit of machining, to fit into the stock rear-end gear housing ("pumpkin") of the SEC. It's almost a bolt in, although on the later "Gen 2" (1986-1991) W126/C126 models, you can't bolt in the diff carrier as it's of a different design ... you have to transplant the gears into a Gen 2 car's pumpkin. In my case I bought a spare pumpkin for the transplant. For the earlier Gen 1 cars, the rear diff carrier is a direct bolt-in from a W116 model. You also have to take care with regard to the ABS.

I believe the European SLs and SECs had slightly shorter gearing depending on the model -- I think it would be a 2.68, NOT a 3.68. The US cars had the taller gearing for better fuel mileage. I don't know if the European car used larger sway bars.

Please double check on the gearing ... I'm hoping you just put a "3" in place of what should have been a "2" in the numbers you were quoting.

Cheers,
Gerry