tranny issues

1990 Merc Cougar Xr7. for quite some time now i've had no overdrive. just recently (only when its cold) the tranny does not want to shift from 2nd to 3rd. my diagnosis, the trannys going?? is this one savable??(with out rebuild yet) another option is i have another tranny out of a 91 t-bird, however its not a super coupe. both motors(my cougars and t birds) are v6 but mine is supercharged and the t bird wasnt. they'll bolt up im almost positive, but will the tranny from the t bird be able to handle the supercharged cat??? ANY feed back would be GREATLY appreciated, thanks in advance to any responces

hi,
n/a v6 trannies have less overdrive clutches in them, and will bolt-up, but will fail prematurely(even for an AOD) because they are not equipped for the extra power your SC has....
I would price a rebuild, and consider art carr as an option...

paul

Overdrive is controlled by a single band not clutches.
Alan

you might want to check to see if the tv cable groumet broke ,its where your throttle cable hooks up to the throttle body. if it let go the third(direct) clutches are probably failing,due to no line pressure rise.the same thing took out the overdrive band assy.if the fluid is burnt its probably time for a overhaul.good time to put the wide ratio gearset in,add more clutches to the packs,and install the wider reverse drum in so you can update to the larger od band.good luck