I have a 2004 F150 4.6 auto, tow package
I just rolled 100,000 miles. It has never had any service to the transmission, and I don't have any problem with it now. Is it safe/smart to change the fluid and filter now?
It seems like a silly question but...
I once had a Ford escort with 160,000 miles on it, and blew the motor, I replaced the motor and changed the filter and fluid in the trans. The car never moved again. The transmission shop said I shouldn't have changed the fluid and filter with that many miles on it.

 

Go ahead and change it. If a trans fails from an oil change, which happens seldom when you look for the TRUE cause, it's because it was on life support anyway. It woulda dumped on you sooner rather than later even without a change. You prevent problems with fluid changes. Do it ASAP is my opinion.

 

Do it ASAP, and get a complete fluid exchange. It's also time to change the differential fluid.

 

+1

 

I got the same truck and the recommendation for trans maintenance is 100K. Shop that does it told me 30K but Ford says 100. I got mine done the first time at 100K and again around 140K. No problems yet.

 

30k is the recommended interval under "severe" service - such as towing. Under "normal" service it's 150k.

 

Thanks everyone.