Differential oil change ??

[Mercedes only]

Hi all ^_^ ...

I have heard and read a lot about Differential oil change .

There is too much and different speak :
Some advised : not to change to avoid noise and break down .
Some advised : add a little of grease to remove the noise and reduce friction .
Some : recommended for heavier viscosity W140 to avoid loss of oil especially in the hot area.

I think that all this talk is wrong and without logic ..

this is first time for an oil change on my car and I wait for your comment and advise .

Thanks ...

 

[Roma_500E]

Hi all ^_^ ...

I have heard and read a lot about Differential oil change .

There is too much and different speak :
Some advised : not to change to avoid noise and break down .
Some advised : add a little of grease to remove the noise and reduce friction .
Some : recommended for heavier viscosity W140 to avoid loss of oil especially in the hot area.

I think that all this talk is wrong and without logic ..

this is first time for an oil change on my car and I wait for your comment and advise .

Thanks ...

Those who say things like that either have no idea about cars or drive cars that have never received proper maintance so to extend life of some parts they try to keep old fluid.

I change differential fluid every season (once a year) I used Mobil Synthetic lubricant which is 75W-90 (if I remember it right).

I do strongly believe that the fluid/oil is crucial thing for every part such as engine, tranny, differential, suspension etc .... If you change fluid frequently with premium brands and your car is well build (which is the case with MB) it will run forever.

 

[Mercedes only]

Thanks .. I've bought two .exactly like this in picture .. 85W/90 Is it Enough ? I hear some noise !! Any precaution ? Any comment ??

 

[gerryvz]

80/90 or 85/90 is fine for the differential. Diff oil doesn't need to be changed every year. I think it's fine to go 20-30K with it, particularly if using synthetic diff oil. The factory spec for the diff oil change (with dino diff oil) was 30K back in the day, and oils have come a long way since then.

Diff oil is very different than regular motor oil and can/should be on a totally separate change schedule.

Cheers,
Gerry

 

[gsxr]

+1 with Gerry. 75W-90 or 85W-90 (or close to that) is preferred. Change every 25kmi or so. Maybe up to 50kmi with synthetic gear oil.

 

[Roma_500E]

Thanks .. I've bought two .exactly like this in picture .. 85W/90 Is it Enough ? I hear some noise !! Any precaution ? Any comment ??

You will need some pump to put it in with this kind of bottle . Otherwise you good to go , it is 1.5 quarts (double check in manual)

Well it depends on the noise and condition (color) of the old fluid so you might need to look for a new differential ...

80/90 or 85/90 is fine for the differential. Diff oil doesn't need to be changed every year. I think it's fine to go 20-30K with it, particularly if using synthetic diff oil. The factory spec for the diff oil change (with dino diff oil) was 30K back in the day, and oils have come a long way since then.

Diff oil is very different than regular motor oil and can/should be on a totally separate change schedule.

Cheers,
Gerry

Thats true but it is just appx. $100 of spendings and you have the fresh synthetic oil all the time my old oil from previous owner was really dark , now i want to be it super clean

Gerry, do you think 75-90 is ok ? or it is better to switch to 85-90 ?

thanx

 

[gsxr]

Fill spec is 1.3 liters IIRC, but the actual fill amount should be such that the gear oil just dribbles out the fill hole, with the car level (i.e., not jacked up on one side).

I believe 75W-90 is a common weight for synthetics, like Red Line 75W-90 or Amsoil SVG, both of which I've used with good results.

 

[gerryvz]

An important tip to remember when changing the diff oil. There are two holes - a drain plug and a fill plug.

Make sure that you remove the filler plug BEFORE you remove the drain plug. That way, you don't drain the diff before you know that you'll be able to fill it up again! You don't want to be stuck not being able to fill your diff back up.....

Cheers,
Gerry

 

[samiam44]

I don't remember on these cars,

But I remember on older benzs. The drain plug is a pipe thread and the fill had a flange and sealing washer. I would hit the fill plug with a hammer firmly on W123/126's and the plug would come out easily.


Michael

 

[gerryvz]

Yes, my direct experience on this is from the 126. About 8 years ago I had a lower 3.06 gear-set installed into a stock 2.47 "pumpkin" and obviously refilled it with new diff juice at that time. Which reminds me, I should probably change my juice.

 

[gsxr]

All W124 differentials have tapered fill/drain plugs. No sealing washers.

 

[Mercedes only]

I don't know how to thank you .

I replaced the oil today and all thing are fine , the old oil was so bad in color and odor ..
But i hear sound, may be like " nnnnnnnnnnn "when i press the pedal and concentrate my hearing with focus it to the back .

 

[Trae]

Just changed diff oil in the 93' with Red Line 75W-90.
Thanks for the write up Gerry!

http://www.500eboard.com/forums/showthread.php?t=7078

 

[nocfn]

is that the newest one Trae? When I did the C126, I think the smell was the dinosaur that made that oil was in there. That oil after 20+ years is quite rancid.

 

[Trae]

Yes, all the cars now have Red Line 75W90 in the diff.
It needed to be changed, however, was not terribly old.