Hi guys, I think i may have had my driveshaft made a little short, i measured it at 59" when i probably should have made it 59.5" or 59.25" Car: 65 skylark with 401 and ST400 installed. The yoke is 3" long and is both IN and OUT of the ST400 short tail by 1.5" with the weight of the car on the wheels. BIG QUESTION =========== So my question is........is 1.5" in the tail enough? Of course the splined shaft coming out of the trans is already sticking out a bit before i even insert the driveshaft so i guess i'm actually a little more than 50% connected to the trans. Can someone tell me if i made a big boob? If i understand correctly the shaft will move more into the trans as the rear end drops. Thank you to all who respond. Gary,
What's the driveshaft connection at your diff? My '71 Riv has a flanged yoke at the diff input where the CV joint end of the driveshaft connects with four bolts. When I converted to a 4spd (shorter), I needed a longer driveshaft. I found a '71 Electra driveshaft in the yard that was almost long enough, but still 3/4" too short. I had a local machine shop fab me a 3/4" spacer that's sandwiched bwtween the d-shaft CV flange and diff input yoke flange. Just had to get longer connecting bolts then. Since the spacer is not part of the driveshaft, it didn't come into play with balancing.
Hi Steve, Good idea! Thank you i'll look into that. If it can be done on mine it will probably be cheaper than getting the machine shop to do up another one. The rear end is a standard 10 bolt from a 65 skylark. Gary,
The A-bodys don't have a bolt-on flange at the rear. I'd suggest getting a longer front yoke. If you ever change to a diffenent rear, like a 8.5 inch or a 12 bolt, you will need the shorter driveshaft. The 4 speed 65-66 GS's use a shorter driveshaft as well.