Fluid Changes
 

I have a 2004 C230 Sport Sedan with the supercharged engine and 6-speed manual. I am trying to find information about when to change the transmission fluid and differential fluid. There doesn't seem to be any information available from the Mercedes owners manual or the shop manual on CD as far as recommended intervals. Any suggestions? BTW, I have 61,000 on my car now.

Also, I am going to do a brake job soon and thought that would be a good time to repack the front wheel bearings. I recall reading the bearings are frequently destroyed just getting them out of the hubs. Seems odd, but anyone have any pearls of wisdom to share?

For the manual transmission and differential they should have a fill and drain plug on them, locate both, open the fill first (to make sure you can get it open), then drain the fluid, and refill with a good quality gear oil.

With only 61k its unlikely that the front bearings will need any service....I am not sure how they are designed on the new cars like that, but I bet they don't need any work for quite a long time yet. My bearings on my W126 went over 250k with no issues. You could remove the oil seal and re-pack/re-grease them, but the bearings should be fine. Get a good seal puller to get the seal out of the hub.

Is it possible to lubricate the supercharger?

Wouldn't it have an oil bearing like a turbo?

It would seem to be a good idea, but I am pretty sure that they do not.

From what I can find it appears most have their own little oil sump....

The supercharger bearings are lubricated with engine oil.

For manual transmission and differential fluid, 100,000 mile change intervals work nicely. Make sure you use the correct fluid in each.

Thanks all for the replies. Good advice.

I think the supercharge is lubricated with its own oil (special oil). See pic from 2004 Approved Service Products.

It is quite expensive.

The supercharger on the M111 engine calls for the same oil (000 989 62 01) as the M271.

I have heard some owners use the General Motors supercharge oil for 1/10 of the cost of the Mercedes oil. However, do your homework by searching around to see what other people are using in the Eaton M45 (if yours has that supercharger).