Thanks

 

The ATF does not need changing as a matter of course but there is a screen filter in the bottom pan that can be replaced and at the same time the ATF is changed. I use only fully synthetic ATF. The dipstick was dispensed with some time ago I beleive the checking point is accessed from underneath using the appropriate length of dipstick for the model that MB dealers keep as a special tool. Not sure if there is a DIY level plug or not. ATF is usually checked when the transmission is hot and in park with the engine running. Overfilling causes flaired gear changes as is to be avoided.

 

My mercedes shop recommends every 50,000 miles(personally I think that is a little conservative). If left unchanged they have seen E-Series transmissions fail at 90 - 100,000 miles. Replacement trans is $7500. I just bought a E430 with 80,000 and have had it changed. Mercedes advertises lifetime capability but practical experience has proven different. Diptick is $45.

Matt

 

When I purchased my '99 C280 about 8 mos. ago, I wanted to change all the fluids. Dealers told me "lifetime" fluid for trans, but I found that all independent garages, which specialize in MB, recommend fluid change. I finally had mine changed a couple of months ago, and in the final ananlysis, it can't hurt and probably helps. The used fluid came out black. Most lubicating fluids have a package of conditioners that are used up overtime even if the synthetic molecular structure doesn't break down. They there is the matter of the filter. If there is a filter, it stands to reason that it will become clogged over time. (Obviously, when I talk of fluid change, I mean filter as well- only $25 for filter kit)
If you replace it, make sure you, or the mech, follow MB procedures. I understand the fluid level is critical.

 

i work for Mercedes and we recommend changing the trans. fluid every 50-60k miles. With a trans. filter and fluid change every 100k. They're different opinions on weather its a lifetime fluid. I dont see how it can be, it goes is bright red, and 60k later(dependind on driving habits) it comes out light brown to even black. The color change is do to the heat, and friction discs engaging and disengaging. The clutchs(friction discs) do lose minor amounts of material every time they engage and disengage, the fluid lubricates and cleans the system. Mostly its a detergent(cleaner). Naturally over time it would lose the ability to clean as it becomes more dirty.