I bought this car new. It has about 190 K on it and has always been serviced by MB. I am embarrassed to say but I just realized that they have never changed the transmission fluid. They tell me that the transmission is sealed for life and does not require service. They also say that changing the fluid could start problems. The car shifts perfectly. Should I leave it alone or insist on the service?

Thanks,

srb1194

 

Dealers have begun recommending a transmission service at about 60K.

If it were my car I would have it serviced. I serviced my 98 at 120K and found no evidence of wear (ie detris in the bottom of the pan). It shifted well before I serviced it and still does. Be sure to use the correct MB fluid. Some people are saying the newer 7sp fluid is okay for the 5sp but if it's cheaper there's a reason. For me cost per liter isn't much of a factor when spread over that many miles.

BTW, I asked one MB service manager what 'Sealed for Life' meant and he said that when the transmission fails it will not be because of bad transmission fluid.

Good luck.

 

do change yourself for about $100+. have independant shop do it for a little more.
have dealer do this for $300+

recommend that you read through the great wealth of info here....

http://tinyurl.com/5qc5hc

 

The dealer is warning me that the new fluid may break down some of the varnish inside the transmission which will lead to problems. By the way it may be a dumb question but without service, how many miles will it last? I know you did yours at 120K but I'm still worried at 190K.

Thanks,

srb1194

 

So your dealer is suggesting 'drive it until it breaks'? That seems to fly in the face of everything I've ever heard about Mercedes Benz. Maybe check with another dealer for a second opinion.

Old notions die hard. It used to be true that when a detergent oil was put into a car which had run on non-detergent oil a lot of sludge came off surfaces. That was about 50 years ago! With modern synthetic fluids that's really not an issue. Further you are replacing the fluid with exactly the same fluid currently in the transmission so no chemistry is being changed.

Since you've owned the car since new you have good knowledge of how it's been driven. If you've driven it normally without any heavy trailer pulling thru the mountains or impromptu drag racing on Saturday nights, the transmission should last a long time. How long? I'm not aware of any accurate data on the transmission's life cycle just some anecdotal comments on these sites.

Bear in mind this transmission is used with the V8 engine as well as your V6 so it's well built.

One of the reasons I suggested the service is that by dropping the trans pan (to replace the filter) you can inspect the bottom of the pan. This is where you can get an idea of transmission wear. A small amount of fine grit (brass or aluminum) or fibers (graphite) is not unusual especially at your mileage. A large amount indicates the transmission may need overhaul. Personally I would rather know of an potential problem so I can plan for it rather than an emergency at a bad time.

Good luck.

 

You make good sense. I guess I'm just afraid it will develop problems after this service. So what you are saying is that there are no detergents that would cause any problems? I've pretty much decided that you are right.

Thanks for the info.

srb1194

 

Let me clarify. The detergent issue I was referring to involved engine oil not transmission fluid. I was using it as an example since it represented the kind of concerns people had back then. While I'm sure that the formulation of synthetic transmission fluid involves some chemicals with a detergent action, they're usually not described that way.

If you want to be cautious one alternative is to do a gravity only change. You have a drain plug on both the trans pan and the torque convertor. Just draining those gets about 95% (7.6 of 8 liters) of the fluid in the system. Many dealers have fluid exchange machines which flush the entire system. The gravity method is gentler on the system. Also, many independent shops use the gravity method since the machines are expensive.

Transmission service gets a fair amount of discussion going on these sites and opinions vary. Doing a search will give you plenty of reading material. There's also a good DIY thread on the subject in the W210 forum on benzworld dot org. It's listed in the 'stickies' at the top of that section.

 

OK I'm convinced that I should go ahead and change the fluid but there is no way i"m going to tackle that job. It's my wife's car and if something goes wrong....well you get the picture.

Thanks again,

srb1194

 

they use mb spec fluid.Your torque converter has a drain so make sure that is drained also.Do not use anyplace that suggests a flush.Drain and new filter gasket and fluid is all that is needed.

 

Thanks for the tip.

srb1194