87bob

Has any one installed or been thinking of installing the manual overdrive I have seen written about in the car magazines. I hate to think of swapping trannies or rear ends it seems like there are to many down sides. The guy on TNN's Trucks put one on a TH400 in a recent show. It appeared fairly straight forward. Remove the tailshaft housing, put on a coupler on the shaft, bolt up the over drive, Rework the crossmember, Shorten the drive shaft, install the shift cable, reconnect the speedo cable. With this set up you could easily return everthing back to stock if needed.

GrandSportC3

Several people - including me - have a Tremec TKO 5-speed overdrive.. We also have a few people with TH700R4's on the forum...

Jvette73

I doubt there is enough room in the tunnel for an O/D unit attached to the back of a standard 3 spd auto tranny. Not on these cars. the way to go is swap it out for an O/D tranny. The TH2004r is the best bet in my opinion. better than the 700 and believe it or not the 200 is proving to be more durable the the 700 on this forum. Different people on here have used either on of these trannys and it seems like there are fewer problems with the 200. Its also a more direct swap and it has a better ratio spread.

87bob

GrandSportC3,
Yeah I know about those who have done the tranny swap thing. Some seem happy and some don't (See todays posts). Some have said I should go with a 700r, some with a 200 like is in the Grand National. Some suggest I go with a rear gear swap. In todays posts there is a guy unhappy with Bowtie overdrives. I like the idea of the manual overdrive on the tranny it is more like the 4+3 in my 87. It can be switched in or out. No worries about TV cable routing/adjustments, lock up/non-lock up converters. When it is engaged I'd get the mileage I want and when I want to get on it I'd have the benifit of the lower rear gear. I'm hoping someone has done it already and will share their expirences with us all.