My 2008 Mini Cooper has only 35,000 miles on it and my shop is suggesting that I change the all the fluids from the brake fluid to the transmission fluid. I looked in the owners manual it says that the transmission fluid is good for 100,000 miles under normal driving conditions. I don't take trips in my car and only use it around town to run errands. Is my shop asking me to do unneeded services?
Millie what you consider "normal driving" is really "severe service" type driving. This type driving means that normal service interval are cut in half, along with the mileage intervals or whichever comes first. Normal service interval for a transmission service on your Mini Cooper is 10 years or 100,000 miles. Since your type driving is considered harder on the mechanics of a vehicle, your service interval will be cut in half to 5 years or 50,000 miles or which ever comes first. Your Mini Cooper is 8 years old with 35,000 miles that has only been driven in stop and go traffic around town. This is a lot harder on a vehicle than most people realize. I think your shop is looking out for your best interests by helping keep your expensive CVT transmission on the road, working as it should.
According to the Society of Automotive Engineers (SAE) all fluids (besides engine oil) in a car that has been driven in a "Severe Service" conditions, it is best to replace every two years or thirty thousand miles. Automotive Fluids MAY become oxidized and their protective additives may drop out of suspension and become ineffective, causing severe damage to mechanical components.
I have copied and pasted Mini coopers notes on severe service below to help you decide what is best for your car. A good rule of thumb about performing services on your vehicle: "Changing fluids in your car is cheaper than replacing metal parts".
Mini Cooper Notes on "Severe Service"
Since maintenance intervals are affected by climate and operating conditions, customers who operate their vehicles under more arduous conditions, or who's driving habits are markedly different from the "Average" motorist should have a more personalized service program developed for them. This will ensure the continued safe and reliable operation of their vehicle.
Because this manufacturer does not specify a Severe Service Interval, the determination of the proper maintenance interval should be left to the good judgment of the vehicle owner and the advice of an authorized service center.
Conditions that will change the frequency and composition of Normal Service:
- Operating in dusty, wet or muddy terrain
- Frequent driving in dense city stop and go traffic
- Repeated short trip operation without sufficient engine warm up
- Ambient temperature extremes
- Operating in mountainous/high altitude areas
- Trailer towing
NOTE : Low mileage vehicles should be maintained at least once a year.