Two. whole. hours.

Topic: Two. whole. hours. (Read 2948 times) previous topic - next topic

Two. whole. hours.

Reply #15 – August 24, 2006, 03:54:40 PM

Quote

then you enter the rear ratio, drive gear teeth (7 for an 88 AOD), tire height, and click "calculate" and it gives you your number.

Do you have a Mustang AOD? They had a 7 tooth drive gear. The Tbird/Cougar AOD has a 8 tooth drive gear. I used a 21 tooth driven gear in my Tbird with 3.73 gears and it was about 9 mph off beacuse I have a 8 tooth drive gear. It would have been dead on with a 7 tooth drive gear. I have a 23 tooth driven gear on there now and it's only about 3 mph off. I guessing that with 3.55 gears and an 8 tooth drive gear you'll need a 21 tooth driven gear.

Two. whole. hours.

Reply #16 – August 24, 2006, 07:40:09 PM

You mean to tell me that Ford actually built a difference into the transmissions between Mustangs and T-Birds, as well as a difference from 89 to 90 (in Mustangs)? I suppose this shouldn't surprise me, given Ford's track record for such things. I'd just like to know why in the hell Ford would make a different output shaft for Thunderbirds. My car has its original AOD tranny (for now). You sure the T-Bird has eight teeth? If that's the case I guess you were right with the purple 21 tooth gear...

Two. whole. hours.

Reply #17 – August 24, 2006, 08:28:10 PM

Yep my tranny has never been out of my Tbird and it has a 8 tooth drive gear. Don't ask why Ford built different AOD's for the Tbird/Cougar and the Mustang. I know Mark VIIs and Mustangs got the AOD with 7 drive teeth and the Tbirds/Cougars/Crown Vics ect got one with a 8 tooth drive gear. I think it's because the Mark VII and Mustang tranny's had a few extra clutches or something. That dosen't make any sense though because the drive gear dosen't handle power.