Ok, everyone under the son has told me to never change/flush the transmission fluid on a vehicle with high mileage if it wasn't done on a regular basis. Is this true?

The guy that runs the local Grease Monkey told me that if it's changed at high mileage and it's never been done before then it will strip the lining of metal shavings and cause the tranny to slip in a week or two. I've heard that Pep Boys won't even do transmission flushes anymore because a lot of folks were coming back with the very same issue. So what's the real story?

Should it always be changed no matter what or only if it's been done on a regular basis from the beginning?

BTW, I bought my Ranger when it had 183,000 miles and now at 210,000 I’ve yet to change the transmission fluid. So far so good.

 

Pretty much what I heard. A flush at high miles can loosen the crap (metal shavings) inside and actually harm the transmission. So, either do it regularly at every 20K or so or not at all.

 

I've heard and experienced the same thing. The way I understand it change it regularly from the start, or not at all.

 

Good to know. Thanks guys.

 

I would just run it till it wont run no more.

 

change the fluid and filter and save the old tranny fluid. if it slipd put the old fluid back in it with a can of seafoam trans tune or lucas no slip

 

The first time I changed my tran oil was at 120K miles. The oil was pretty dark. From then on, I change tran oil every 20K miles and have had no issue. It's an easy job after all.

94' B2300, 243K miles