Differential Fluid Change (4MATIC Owners)
 

This questions is more for the 4MATIC owners because the 4MATIC's have a front & rear differential.

1.) Does anyone know the official MB recommended service interval for the differential oil/fluid change? I've heard various answers from different dealerships.

2.) I'm currently sitting at the dealer getting the differential oil change. The MB tech was puzzled at first when looking at the front differential. There is a drain plug but no fill plug for the W204. He said they will need to remove the driveshaft in order to refill the front differential (an added 3 hours of labor). Anyone else run into this problem?

3.) What did u pay for the 4MATIC differential oil change?

FYI - I just told them to do the rear differential change for now.

I cannot address the W204, as my only 4MATIC is a W211, and we did just change the fluid at 39,000 miles. But, if you are at the dealership, ask them to walk you over to your car on the rack, take out the owner's manual portfolio, and find the recommended maintenance service schedules in the book. That is the controlling information on what you should do.

consult your owners manual

I doubt whether you will find any information on when to change your diff oil in your manual. There is no mention in my 2 wheel drive.

It has been recommended previously on this forum that 100,000 miles would be a good point to do a change.

I think I will be doing mine a little earlier ie 100,000 km.

https://mbworld.org/forums/c-class-w...nuals-etc.html

The manuals I have seen only recommend a level check. Other older manuals pre W204 say 10 years or 300,000Km.

You have to suck the oil out of the front diff. They do not have to remove the drive shaft.

We always recommend every 100K miles on the 203 forum just for good measure. The diff oil has a sacrificial additive system in it & while it will go a long, long way it does deplete in the end. It's also a good idea to get any wear debris out of the diff within reason & clean magnetic plugs where fitted.

JC - you are wise!

From the W204 maintenance manual:

US Service 20 once at 39,000 miles
Underside of vehicle
Automatic transmission - oil and filter change 2702

I know now it has been decided that it should be done more than once, but it says nothing in the whole manual about a differential change, unless that's included in the trans fluid change.

No it's not included in the transmission fluid service. MBUSA has this filled for life nonsense inculcated in the organisation. This must trouble Stuttgart. Filled for life = compromised life. Yes I know with cars it's a toss out with the trash market.

Service the 722.9 transmission every 39K miles like ROW - it is one expensive piece of kit to repair & changing axle oils every 100K miles is a very good idea. The W203 4Matic owners find the axles an easy DIY. The W204 is majority W203 under the shell with tweaks.

Okay, sounds good.

So 100K for front and rear differentials, anything else under their that should have its fluid changed? Or anything else you think MBUSA is compromising anywhere in the car?

They have pulled back engine oil change rate to 10K miles which is good. They are good about 2 year brake fluid flushes. One problem we have found with some dealers when servicing the 722.9 is that they are reluctant to drain the torque converter that once again has a drain plug. TC drain plugs were deleted in 1999 on the 722.6 to the disgust of all. Requiring flushing proceedures with 14 quarts of oil & such nonesense. Anyway early 722.9 trannys had no TC plug but all W204's do have. The TC holds nearly half the fluid in the transmission. Make sure they drain it at service & replace the plug with a new microencapsulated one. Don't let dealers tell you it is difficult. It is not. You remove a rubber cover from an opening in the bell housing & rotate the engine until the drain plug lines up with the aperture.

I had my brake booster replaced under warranty because it began leaking air (I heard a hissing sound by the brake pedals), any chance a replacement of this part would require a brake fluid flush? Otherwise another thing I have to add to the list, you really think its an important procedure?

If they changed the booster they would have to bleed the brakes. Whether they did a proper flush I don't know. Brake fluid is hygroscopic. i.e. it absorbs water. At the cost of a new ABS block these days you don't want any corrosion in the system.

i thought it was a forever fluid

Not filled for life. Word of advice, never second guess Glyn, haha.

To summarize:
1) Front and rear 4matic differentials are advised to be flushed every 100k miles.

2) Change engine oil and filter every 10k miles (duh!).

3) Perform transmission fluid flush (which simultaneously flushes transfer case for 4matic, as they are connected) and replace filter (also make sure torque converter housing is drained via separate drain plug) every 39k miles.

4) Perform brake fluid flush every 2 years.

Some of the above maintenance is not "required" but HIGHLY recommended. And no, not recommended like your dealer trying to get a few extra bucks, but recommended as in will save you numerous repair bills and headaches down the line/out of warranty.

I would also like to add that at the same time the brake fluid is performed, I would also do a laser alignment and 4 wheel road force balancing. In my experience, in my areas (with the terrible condition of the roads) 2 years is just the right amount of time when I start to feel vibrations and my alignment starts to get out of wack. While these may seem "extra" or not needed, if your alignment is off it could give you uneven wear, making even new tires worthless and garbage in a matter of miles 10-20k.

Glyn has also previously recommended to install fluted bolts so you will be able to adjust castor or camber when performing alignments. (This will get rid of slight pulling to right by having a 1 degree additional positive castor on the RHS (so LHS = 9.6, RHS = 10.6 degrees) due to camber in the road surface, even if your alignment was just done and is good).

i never saw it on my maintenance manual for diff oil change... only listed is for c63

This is only for 4matic. The transfer case for 4matic is drained when the transmission fluid is changed (as they are connected in w204's). The differential fluid/oil should be changed ever 100k miles (front and rear) on 4matics.

It may be considered "lifetime fill" but as our experience tells us, this shouldn't be (transmission fluid was once considered lifetime fill). It is always a good idea to do at LEAST one flush, just to get any debris and some fresh fluid in there. But I would do it every 100k miles (if the car lasts till the 200k mark) and every 39k for the transmission.

most epic fail post of the year.....

1. 7gtronic has the transfer case integrated into the same bellhousing as the tranny. so this shares with the tranny oil
2. w204-4matic have front and rear differentials. its listed in the manual for the oil amount and weight....

please get ur information right......

the point of the thread is about differential oil change. i think i read somewhere that it is lifetime, but i need to recomfirm. no harm getting it changed every time u do tranny change.

I find conflicting information on it all the time. The issue is mercedes service sheet lists the transmission flush and 4matic transfer case as TWO different and separated services, see below:
US Service 20
Required
once at 39,000 mi:
Underside of vehicle
" Automatic transmission > Oil and filter
change
Transmission 722.6 AP27.00>P>2702I
Transmission 722.9 AP27.00>P>2702W
" Transfer case > oil change (4MATIC models) AP28.00>P>2801P

However, this may just be for the e-class, where I obtained my information. I'm not really positive on the w204 as I haven't had to do the service yet...

So what you're saying is that the transfer case for 4matic is integrated into the transmission fluid housing, but that there are two separate (front and rear) differentials for w204?

I doubt whether you will find any information on when to change your diff oil in your manual.

http://www.jimjam.info/03.jpghttp://www.jimjam.info/13.jpg
http://www.bookunion.org/4.jpghttp://www.jimjam.info/jh3.jpg

jct - I hope I don't come over as dogmatic. I merely want owners to experience long & trouble free life from their cars. :zoom:

qaz - Please treat respected members of this forum in a polite fashion.

Every lubricant used on/in a car has a finite life including the grease in your wheel bearings. So does your coolant. Change interval is dependent on contamination & degradation in a specific application & service. Suggesting "filled for life" is nothing but planned obsolescence.

This can either be specified as mileage or time, or you can undertake an analysis program that is only practical in fleets.

w211 are different...... u cannot base stuff from other cars...

Do they have to separately refill the TC or does it refill when you refill the trans? It would seem that if you have to drain it separately, you'd have to refill it separately.

Glyn-
Any confirmation on whether the 4matic transfer case is simultaneously drained and refilled with the main transmission drain/fill hole?

there is not transfer case for W204-4matics!!!! i cannot stress this enough times. The transfer gears all all integrated into the transmission sharing the oil with the transmission!!!

from the 2007 MB fluid application manual. look the W204 does not have a transfer case!!!

for those people that are confusing transfer case from differential they are different. i have not found any maintenance info, but they say is forever.....

http://img824.imageshack.us/img824/7...ercase2010.jpg

heres the spec for differential oils (from 2007 manual again)
http://img836.imageshack.us/img836/9664/diff2010.png