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Transmission fluid change at 54K miles

So I know that you should change your transmission fluid every at 25K miles. I just found that out after changing the fluid for the first time at 85K miles in my Ford Escort. Some even say that you shouldn’t change it at all if you have not changed it periodically and it has that many miles. So on my other car, a Mercury Mariner, I have 54K miles and no trans problems. Should I change it now or is it too late?

I disagree that 25k is a must. I do it at 50k unless the manual says to do it sooner. So 54k is fine.

What I read is that if you have never changed the transmission fluid and you have around 75K or more miles, then you are better off leaving it alone because all the dirt and gunk is actually helping keep your transmission from slipping. If you change the fluid, then you may be doing more harm than good. However, eventually the gear shifting starts getting rough. The intent of the original question was to determine if I have missed that window and 54K is too late. It sounds like it isn’t.

That’s a myth. What happens is people with a troubled tranny finally get around to changing the fluid, and the tranny has a problem (it would have anyway). They then blame the fluid change, rather than the lack of maintenance, for the problem.

The owner’s manual for my 99 Accord says to first do it at 90k. Does that mean I do it every 90k? No, I do it every 15-20k to be safe, but I think you should be fine.

I agree with Tex, if the fluid change “causes” a problem, then it was going to break sooner or later anyway.

A lot depends on your driving style. In general, I would say 15-20k is too often, unless you are carrying heavy loads or pulling a trailer. 35-40,000 as recommended by most experts, including Transman, is about right. My Toyota also has a very long interval, so I will change it earlier.

Car maufactirers who have NO change recommendations, don’t care about their customers’ long term interest.

Drop the pan, clean it out real good and take note of any trash in the pan (Brass, aluminum, steel,and chunks of fiber material)change the filter and refill. Do this every 25-30k miles regardless of what the owners manual says.

transman

Do it now. Do it yourself or take it to someone and make sure the correct fluid is used:

The wrong fluid can ruin a transmission very quickly