How many miles has the current fluid have on it?
I changed my red Cougar two weeks ago, at 190k; It made a nice feel change, as well as a MPG change. (The mpg thing could be due to the seafoam,too, but my trans was not hooking up well at all)
You will definately know when you drop the pan what kind of condition your tranny is in; the magnet in the pan collects most of the bad news for you...
Pull some of the fluid, (I use a basting syringe and a piece of tubing for such things) and see how it looks.
If its red and clear, you probably dont need to change it. depending on miles since it was changed, of course.
If its cloudy, a change will probably help.
If it is full of particles, and cloudy, or brown, changing it will probably make your tranny not work. At that point, the crud is probably all that is making it hook up.
Note the word probably in there; every car I've ever had has been different; all have eventually had tranny probs...But I've never had one fail that had clean looking fluid. The two that had cloudy/crap in there, both failed after a fluid change. The plates were gone, pretty much.
My 190k 4r70w I changed last week was cloudy, but no particulates. I think somewhere down the line some mercon 3 got put in to top it off, instead of mercon 5. That was the slippage prob I had I think. It started after a 'friend' helped top off fluids one day; this the same friend that overtorqued the pan bolts on one side, making it leak for the last year. Fixing the pan fixed my slippage, either because of the fluid, or the fact it stays full now...
These cars last amazingly well; even with all the miles, mine (both cars,now) will still bark third, if I burn first and second!!
Red '96 Cougar XR-7 240k mi. '02 4R70W, PST DS : '03 PI engine, 04 maf, 24lb injectors, 2.5" exhaust, '02 4r70w + Jmod, DirtyD0g TC + cooler + 3/8" lines, 255 walbro fp. Alpine system.
Black '96 Cougar XR-7 (Lazarus) 210k mi PI Intake, '02 4R70W, Jmod, PST DS, GrogTune, Konis, Mark LCA+Poly, racecougar Custom Engine Chain, and JL and racecougar Bracing.
Black '97 Tbird Limited Edition, '02 4R70W, 255 walbro, PST DS, PBR Brakes&SS lines, Toicko Blues & Springs, GrogTune.
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