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Automatic transmission oil change

I bought a 1999 Mercury Grand

Marguis in January 2008 (I am the second owner) with 26995 miles on it. I know have 36278. I am taking a 2000 mile trip this year. Since the car is now 12 years old should I change the oil in the transmission or is it ok for now. In others words is the transmission oil affected by age as well as miles.

The car was very well maintained by the previous owner. If I do need to change the oil would it be better to take the car to the dealer or a transmission shop.


Yes, take it there. Keep in mind that if you take it to a transmission shop you might “need” a new transmission. When they’re done with it you really may need one.

A dealer might put the right fluid in it.

There is nothing wrong with changing transmission fluid due to it being 12 years old. It’s probably a good idea. This could be a “why bother asking” type of deal to some of us.

The transmission fluid should be changed about every 5 years or 50-75k miles. You said the previous owner kept up on the automotive maintenance, check to see if they kept records, maybe in the glovebox. As far as where to get it changed, I would take it to a dealer personally. They will know the proper procedure to either drain/fill or flush the fluid.

The trans fluid needs to be changed every 30k or so miles. That is the best transmission insurance that you can buy.

Either the dealer or a transmsission shop (preferably a good independent shop) is fine but with a caveat. Do NOT have a flush only performed. The pan should be dropped and cleaned along with changing the filter first.

Off the top of my head I don’t know for sure but many late model Fords have a drain plug on the torque converter. This helps quite a bit when removing old fluid if a flush is not performed.

I would trust an independent transmission shop before I would thrust the kid on the grease rack at the dealership…Pull the transmission dip-stick…The fluid should look clean and pink and have no real odor…if that’s the case, drive on…Nice car by the way. I think the service interval on that tranny, in normal service is 60K miles. Honda owners will tell you 30K but they have good reason to believe in that…

I’d say change it. The transmission in your car seems to be susceptible to “torque converter shudder”. Keeping the fluid fresh and clean helps to prevent this.