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Transmision Fluid

I just recently started listening to your radio show and I love it. I have a 2002 oldsmobile alero. It has 110,000 miles on it. It runs perfectly fine. I have never changed the transmission fluid on it and I have heard that if a car has 100,000 miles or more and that the tran fluid has never been changed that it should be left alone. Should I change it or is it true that changing it will cause problems to my transmission?

You will not get Tom and Ray on this forum; only an assortment of people who are willing to help.

You should change it. That story about causing problems at this point is nothing more than an old wives tale that is made more dramatic by the internet.

Check your owners manual and check your fluid. If the manual says change it, change it. Drop the pan, change the filter and refill with Dexron VI. If the fluid is brown or black, change it.

I would recommend against a flush, just a drain and refill with filter change.

If the owners manual doesn’t recommend a change interval and the fluid is red, you should be OK.

People here are NOT Tom and Ray. Just regular folks…some are seasoned mechanics…some are back yard mechanics…but we’re ALL car enthusiasts…At least those of us who don’t believe that we’re all going to die in the next 3 months because of the Cancer Causing Cars are killing us.

For manual transmission…Leave it along…unless GM is still using ATF in their manual transmissions. Then I’d read below.

For automatics…
What does the owners manual say. Forget that…change the tranny fluid every 30-50k miles no matter what. Any longer and you take the risk of shortening the transmissions life.

This question and ones like it are asked on a weekly, if not daily basis. Use the search feature.

In short. First, ignore your owner’s manual. Whatever it says is likely ridiculous regarding the transmission. The pan should be dropped and filter changed every 30K miles. Whatever damage you have done by leaving it for 110K is already done. All you can do now is help it. I would probably drop the pan, change filter, and then have a full fluid exchange done.

Transmission service-related nightmares come from a couple of things. One is that people do what you do - ignore it. Then when they start having problems they have it serviced - too little too late. (I understand that you imply no problems). The second is poor service - putting the wrong fluid in is a very common one.

Take yours to an actual local transmission shop and have it serviced.