i am getting a little angy with my 1971 GS stage 1 car. after fixing several problems with this car due to the fact that it had sat for a LONG time without running, i have had another disaster with this car. the drive shaft fell out (at the rear end side) last weekend. i was travelling 55 mph and had no idea that it was about to let go. there was a short amount of vibration and then WHAM WHAM WHAM....... anyway. after inspecting the the drive shaft and the rear end... here is the damage. the driveshaft is kinked. it struck the under side of the car where the seatbelt bolts are and got kinked. also a weight was knocked off the drive shaft so that has to be rebalanced and possibly replaced. also at the rear end, the retaining bolts and the collars are in place. however they have been slammed into the flange pinion, breaking the area of the flange pinion where the bolts go through. the bolts are loose on the back side of the flange pinion, but all of the hardware is in place. the u joint is a new style of u joint (porbably replaced when the car was restored in 1994-1996) and there is no corrosion on the u joint. the end caps are missing, but that is it. HOW THE HELL DID THIS COME APART!!!! did the bolts loosen on the retainging hardware, allowing the u joint end caps to come off and then allow the u joint to wiggle out of the flange pinion? also the flange pinion has to be replaced. can this just be replaced without the rear end having to be diassembled? or does the whole pinion gear and ring gear have to be re-alligned after that bolt on the flange pinion is loosened and the flange pinion replaced. also the exhaust is smashed and there are some good sized dents in the floor but no holes. what a day......... any help would be appreciated. thanks john
John , sorry to hear about your trouble. Without seeing the rear It is tough to say what happened. I had a mustang that ate u joints with shocking regularity. I solved the problem by selling it. I had a new drive shaft made down in Manchester this summer when I swapped out the 8.2 inch rear in my 64 for a 8.5 inch out of a 72 skylark. They had it done over night. They told me the rubber isolators built into the factory drive shaft will fail eventually maybe yours gave up and that was the root cause. Any way they built an new shaft for me, it fit great and the price was around 300.00 . The name is Gilbert Driveline , Masabesic street in Manchester 603 623 3061. The owner has a camp up here on Winnisquam , nice guy. I also have the old 8.2 rear on a stand in the garage , the pinion yoke is still there so if you need it you are welcome to it. Does your car have a 8.5 or a 8.2 in it? I don't know if they will interchange but if you want to look , swing by and take a look. If not Gilbert may have one . Check out the guys at Kar kraft down by wal mart. Nick and Tom are great guys . they can help you out finding the stuff you need, Tell them I sent you . I am leaving for the air port tomorrow morning at 11:00 sall in the AM and you are welcome to anything i have in the garage. I also have the old drive shaft that is almost certainly the wrong length but you are welcome to it if you need it.
The Shaft I agree with Tom that its time for a new shaft from a drive line repair shop. Any shaft that has fallen out at speed is BENT! Unless you can find the exact length, ready to install, known good driveshaft then used will work. The reason yours came out is the same reason they all fall out after someone replaced the original u-joints. The u-joint caps at the pinion flange didn't have the snap rings installed on the caps (common mistake) hence the u-joint in the shaft is in tact but missing only the two caps at the rear end. I do have a "used" spare pinion yoke and strap kit off an 8.5 I stripped out if you need. I also have a new pinion nut and seal as well. As a rebuilder I would suggest replacing the crush sleeve as well (which requires much more work and detail) but you can replace the yoke without it if you don't over tighten the pinion nut and place too much preload on the bearings. I would suggest taking it to an automotive shop but most so called mechanics, sorry, "technicians" just replace the yoke and nail it down with an impact gun anyway.
transmission tail housing Don't forget to inspect the tail housing on your transmission. Have see a few driveshafts come out and sometimes result in tail housing cracks. Good luck
thanks for your suggestion. when it goes on the lift, i will have them check it. i will keep you informed. john
