Hello All,

I have had to replace the pinion seal on my 1950 Olds 88 rear end and do not remember the torque requirements for the pinion nut. Any one got that info??
Thanks, Bill

 

You didn't by chance mark the nut before you removed it? I believe they are all torqued differently because of shims / spacing.

 

mark the nut and flange with a marker and count the exact turns of the nut somewhere around 10-15 turns or so...replace seal lubricate everything and put the nut on and tighten it the same amount of turns as you removed it

 

plus or minus one turn should be easy to get to. One turn too loose would be obvious, and one turn too tight will probably never happen. Therefore, you really only need an alignment mark on threads and nut. Restore to the same position or one snick tighter. [barely discernible motion].

If it was not marked before dismantling, well, you are kinda screwed. You can guess a the torque and final setting, but it should be done by an expert, reading the pinion spinning torque as you go, with no carrier or ring gear in place. The problem being, if you go too far, you have to dismantle, put a NEW crush sleeve in, and start over.

Therefore, if no match marks were made beforehand, you should probably take it to someone who has done 100's and pay for their expertise.

 

I don't have the manual for 1950. The Oldsmobile shop manual for 1955 does not show any torque value for the pinion nut. It describes the procedure that you have already been given. It says that after getting it back to the original position you can go 1/16" additional. It also says that the bearing pre-load friction should be in the range of 15-20 inch-pounds, and in no case should exceed 25 inch-pounds for a unit which has been in service.

 

Thank you all for your info. I think I have the procedure I need.
I really appreciate your help.
Bill

 

It looks like I am going to need a new crush sleeve. Does anyone know where I can get one for a stock 1950 Olds rear end? Thanks, Bill

 

A new crush sleeve should not be necessary unless it was over torqued and crushed enough to make the pre-load too much. If it was not over torqued just re-torque/install the nut with locktite on the threads. If you cannot find the exact torque value for the year, make and model use the spec from a pinion of similar thread and diameter.

Sorry but I do not know the exact torque value. Good luck!

 

I was going to suggest http://www.drivetrainspecialists.com/ or http://www.ratechmfg.com/toc.htm

 

Thanks everyone. You all are a wealth of information.

 

There is NO TORQUE rate for the nut on any pinion with a crush sleeve. The rate is how much it takes to crush the pinion sleeve. SO if you are replacing the seal you will never be able to gwet the same amount of torque on the nut it had from the NEW crush sleeve installed from the factory.

So here is what you can do - USE RED LOCK TIGHT and snug up the nut so there is no in out or up down play in the pinion... If you had marked the nut to thread you would go back to that spot and maybe a 1/8 to 1/4 turn on the nut. If it ever feels tight at anytime in the reinstall of the nut it will need to be backed off a bit to a smooth turn. When satisfied with the nut position and pinion spin feel...Stake the nut in place with a pointed steel punch where the thread meets the nut. Do this in about 2-3 spots. This will prevent the nut from backing off which is what the high torque rate from the crush sleeve being crushed would prevent from happening when spirited driving comes in. IE (drag racing, burn outs, etc. )

Jim
J D