I have a 04" TJ that has 152,000+ miles on it and I have never had the automatic transmission serviced.
I pulled the radiator out yesterday and noticed the tranny fluid was pretty dark. Dark marroon to almost brown.
I figured I should get it serviced because along with the no service thing, I was having a issue.
While on cruise control and going up a slight hill, at 65 miles per hour, the tranny would down shift to second gear. Not all the time, but enough to bother a person.
So I called a couple places, Jiffy Lube was one of them. After explaining all the details, the guy tells me that in some cases that after a flush, some people experince transmission slipping issues.
That maybe I leave it alone and hope for the best?
Risk doing a flush, then having to do repairs?
I worked for Jiffy Lube while in college back in the late 90s. I performed many transmission flushes and filter replacements. As far as I know we didn't have any issues. You could do it yourself. Here's my write-up:
The machine does not create any pressure inside the transmission, it has a small pump that pumps fluid into the pan.The tranny's own pump does the flushing.
I've literally done over a thousand trans flushes and never had one come back.