This is a photo of the tranfer case oil I drained from my 99 ML 320 with 95K miles. It's black but has no metal shavings in it and no mettalic look to it at all.

Questions:

1-Isn't this oil kind of dirty? Although that may have been the color when it was new.
2-If it is dirty does it affect it's performance with respect to the life of the transfer case?

Mercedes says it never needs to be changed. Is that because:
1-They are telling the truth?
2-They want us to think that our vehicles don't require maintance for certain components and use that pitch to sell the vehicles?
3-They want to sell transfer cases and have customers incurr service charges to replace tranfer cases because they wear out from lack of any maintainance?

It't the same situation for the "sealed for life" transmissions.

My trans fluid was about that color when I changed it at 80K miles except I had about 1/8" of sludge on the bottom of the trans pan.

I wonder if Mercedes condiders life of a vehicle to be 100K miles. I tend to put 200K miles on my vehicles and change all fluids and filters regardless of who says it doesn't need changing.

__________________
Ray
1998 Mercedes E320, 200K Miles
2001 Acura 3.2TL, 178K Miles
1992 Chevy Astro, 205K Miles

Ray,

I changed my transmission fluid at 75K. It was very dark too but the pan had no sludge and no mettallic shavings.

The issue regarding changing the automatic gearbox oil has been discussed before and people more knowledgeable than me feel it's not necessary. I just feel better having changed it and with my cost for the MB synthetic fluid like $7.00 or $7.50 per liter I could see no reason not to change it.

I'm just skeptical of manufactors that say preventative maintance and service is unnecessary. Maybe I'm throwing away money on the stuff I do; fortunately I don't mind spending the $ on such stuff.

Ron,

You and I both think alike, I consider frequent fliud and filter changes cheap insurance. I feel that I am negleting my vehicles by not performing preventive maintenance. I've even kept up on the oil changes to the last two vehicles just before I donated them.

Regarding Mercedes recommendations not to change certain fluids, I just keep reminding myself of the letter from Mercedes recommending pure synthetic motor oil for FSS vehicles. This was for my 98 E320 and the letter was dated March 2001. It took them three years to realize that conventional motor oil was not good for 10-20K FSS service interval (I was using conventional oil at 3K intervals prior to this letter). I might be throwing money away but I will stick to my 5K oil change intervals using full synthetic motor oil.

__________________
Ray
1998 Mercedes E320, 200K Miles
2001 Acura 3.2TL, 178K Miles
1992 Chevy Astro, 205K Miles

Ray,

When I got my ML or shortly thereafter I asked what kind of oil was in the ML that was an AMG model. They told me it was factory filled with synthetic oil mobil one; so I figured if it was good enough for an AMG motor it was good enough for my motor. I change oil every 3500 to 4000 miles. And if you think that's bad I change the oil on my 97 Porsche every 2500 miles and that's 12 quarts of Mobil One.

Hi all. I have a 2008 GL 320 CDI. I asked the dealer about changing the transfer case fluid. Was told its 500.00 labor plus parts as it takes a " special machine " to change the fluid. Please. I did it myself no biggie, just used some suction gun, looked like an old grease gun but for fluids. My GL does not have a 2 speed case. ( who does? ) and it took ONLY half a quart! ( that's .5 quart for the record ) And it was brown! Wow that little bit of fluid works hard! I think I'm going to change it every year now.