Pinion Nut Torque • The Dodge Challenger Message Board

by **spitfire9137** » 30 Sep 2004 1:06

Anyone one know what the pinion nut on a 8 3/4 needs to be torqued to?

by **dave-r** » 30 Sep 2004 9:32

There is no set torque as such. You tighten until you have a specified bearing preload which is measured by turning the pinion with an inch/pound torque wrench. Will have to look up the torque you need but it might be different depending on the pinion type you have?

There are three types of pinion you might have. If it is a step type pinion you require at least 240lbs of torque on this sucker. Preload is set with shims.

If you have a tapered pinion with the crush sleeve you need at least 170lbs. You have to crush the sleeve under it until you get the correct preload setting. You can buy a shim type insert to replace the crush sleeve if you want as you can only use a crush sleeve once.

by **dave-r** » 30 Sep 2004 9:43

OK.
The measurement for bearing preload is 20-35 inch/lbs for new bearings and 10-15 inch/lbs for used. This is without the axles in place of course.

It does vary from pinion type to pinion type but these figures will get you in the ballpark.

Just make sure you have reached the minimum 240 or 170 lbs/ft on the pinion nut to get this pre-load depending on the type you have.

Maybe it is time you bought a workshop manual? :wink:

by **spitfire9137** » 30 Sep 2004 16:32

How would I go about figuring out what I have, I think the casting is 742.

Guess I need to find a shop manual.

by **dave-r** » 30 Sep 2004 18:43

If I remember correctly the 742 is the large stem step pinion that adjusts preload with shims.

I will PM you with some details that will help you.