Re: Help. Pinion shaft torque spects

Posted by gone1951 On 2008/7/5 12:48:11

Thanks for all the response. I have a few more questions for you guys. Does the yoke bottom out on a shoulder cut on the pinion shaft? In other words when you torque the nut to the 200 to 300 foot pounds are you applying that pressure to the bearing or are you just tightening the the nut against a shoulder stop on the pinion shaft behind the yoke. With out some kind of shoulder it would be like tightening a wheel bearing nut to 300 pounds. Way too much. The book says wheel bearings are supposed to be torqued to 20 foot pounds and then backed off one flat of the nut. Sense I'm not replacing any of the internal parts the idea of a spacer installed in front of the yoke makes good sense to me. It would allow for the crush sleeve to crush a little more hence resetting the bearing preload.

A side line story to this is I once replaced the pinion seal on my 1955 Olds 88 and was not sure how tight the nut should be so I set it like you would set a wheel bearing nut. Needless to say the nut was not tight enough and backed off because of normal vibration. I was on a trip and noticed some slop in the drive train but kept on plugging a head . I got to where I was going and pulled off the freeway. I got a couple of blocks and the nut fell off. The whole drive shaft pulled out of the differential and dropped down and fell out of the car. Couldn't believe seeing my drive shaft on the street from my rear view mirror. That's mainly why I am paranoid about doing this again. I'm really lucky this happened at 10 to 15 MPH on a surface street and not on the freeway at 75.


Bob