Has anyone ever had any trouble with the draveshafts with the rubber damper in them? How do these work, Are the two pieces of driveshaft held together only by this rubber I assume? Has anyone ever had one go bad and slip? Is there a way to have them rebuilt like an engine damper?

 

They are 2 pieces bonded by the rubber, eventually they disintegrate. Not good for performance applications.

 

Yes, the rubber does fail, and while I assume they could be rebuilt (they were built originally...), I am not aware of vendors who do that. Most people who experience failure replace them with solid shafts.

 

That is what I am trying to decide. When I restore the Jetfire I am wondering if I should get a solid shaft made for the back section or live with the original. It don't have a problem now but we plan to trailer this car down to the Smoky's and other places to drive around. I just want to avoid any possible problems. I am not sure I ever had a car with this style drive shaft to have experience with one failing.

 

Pretty much every Olds with an automatic came this way. I've certainly never failed one, and I've beaten on a bunch of AT 442s. No, failures are not unheard of, but they are rare. I was curious about your driveshaft photos on the other site. I'm surprised a 4spd Jetfire has this rubber in the driveshaft.

 

Did automatic 442's have them in 70-72? I know the W-30 automatics did not have them. I will likely just use the "best looking" original one I have for the Jetfire. My original has really heavy pitting on it so I will likely use another one.

 

Joe, what year AT's are you referring to ?

 

Eric:
I've owned two '71 supremes and two '72 supremes and all had the 2-piece drive shaft with the rubber sandwich. I never had any problems with my cars, but my engines were mild, 350 cid builds; probably less than 300 HP and all were automatics. I think the rubber insert helps reduce vibrations if the driveline angles are less than ideal.

Rodney

 

Mine is only 215 HP with 301 torque. I want to believe i will be fine.

 

I have a nasty shifting TH400 that managed to torque the 2 piece shaft so hard it out of phased the yokes. This is how they (begin to) fail.
If your J Fire doesn't have a ton of torque your likely OK as long as the shaft looks serviceable. Just keep an eye on the yokes. That rubber is approaching 60 years old.
Or have a solid metal or aluminum shaft made and hang the relic up for wall art.

 

My '66 did the same thing after the engine rebuild.

I suddenly developed a vibration & thought maybe the trans mount or u-joint was on its way out.
Upon inspection, the driveshaft was rotated in the rubber just under 1/8 turn.

By sheer luck, there was a solid shaft of unknown origin in my dads garage attic of the correct length.
Swapped over the yoke & new u-joints... it's been vibration free for many years.