Changing Fluids



While in my friendly Mercedes dealer?s repair department, the Service Manager pressured me to change my fluids: coolant, brake, transmission, etc. The owner?s manual does not list changing these fluids. Is this a scam?


That would depend on how old/many miles are on these fluids.



What year is your car and how many miles on it?

If your car really needs these fluids changed, the garage may be doing you a favor by suggesting it. However, you can get this work done for considerably less by an independent mechanic who is familiar with M-B cars.

In the absence of any other info, most here will recommend changing engine coolant every 50,000 miles or so, changing Automatic transmission fluid and filter every 40,000 miles or so, changing brake fluid every time the brakes are done. Power steering fluid lasts a very long time and keeping it topped up is important. If you do work on the steering, the fluid should be replaced.

Your owner’s manual was written in Europe and there the governments put great pressure on the carmakers to really stretch these drain intervals, often at the expense of the car owner and vehicle life! I recently rented a car in England and the manual said to change oil every 20,000 miles or once a year!! It did not even specify synthetic oil!

I think your dealer is more profit motivated than “knowledge-based care” motivated.


Does your owner’s manual have a maintenance schedule in it? If not, it wouldn’t surprise me that it isn’t listed there.

Yes, coolant, brake fluid, and transmission fluid should be changed routinely. This isn’t a scam unless you recently had them changed.


The car has 21,000 miles on it and it is four years old.


joe; at that low mileage I would only change the engine coolant. Please double check with your owner’s manual, and at least do what’s in there to keep the warranty valid.

To change power steering fluid and brake fluid at such a low mileage is rediculous!

If you live in San Francisco have been going up and down hill all the time since you got the car, you may need the transmission fluid changed. Otherwise, forget it for a while till you have 40,000 miles on it.

Enjoy your car and don’t let greedy “service” managers scare you!!


If the brake fluid isn’t a silicone base brake fluid, then changing it was a good idea. Regular brake fluid can become contaminated from absorbing moisture from the air. The service interval for replacing the transmission fluid and filter is at 40,000 miles. So that service wasn’t required yet. And I highly doubt the additive package in the antifreeze has been used up in 21,000 miles. So that service wasn’t required.



The only one that I would be concerned at given low mileage but age is brake fluid. It absorbs moisture causing poor brake performance and corrosion of expensive parts.