rear-end question ??
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,040
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rear-end question ??
what is the proper bearing pre-load for a stock "71" pinion ??
is this the correct procedure to set pinion pre-load,this is with a solid spacer,NOT a crush sleeve
torque pinion nut to 125 lbs. then measure force required to turn pinion nut with a ( inch pound ? ) torque wrench.
is this the correct procedure to set pinion pre-load,this is with a solid spacer,NOT a crush sleeve
torque pinion nut to 125 lbs. then measure force required to turn pinion nut with a ( inch pound ? ) torque wrench.
Tech Contributor
Joined: Aug 1999
Posts: 15,176
Likes: 3,990
From: Connecticut, USA
Re: rear-end question ?? (1971corvette)
Depends on if you're using new or re-using the old beairngs. The spec's are all over the place form 5-6in/lbs for used to 15,25,or 30 for new. I wouldn't try and reuse old beairngs firat of all,put new ones in since you have it apart. I set them to between 15-17 inch pounds without the carrier in place,just the pinion,no seal, no sleeve until you have the correct pattern.
Sounds like the correct procedure for a solid but I haven't used one yet. A friend just did this yesterday. He used an impact gun to draw in the bearings. He started out with about .010-.015" oversize compared to hte original crush sleeve. When he got to zero end play he still had no preload. He measured it with a inch/Lb wrench and it was about 2in/lbs. He then removed .002" in shims, applied 125 ft/lbs and the drag increased. He was working to about 15"/lbs the last I heard so that must be the way to do it. Let me know how you end up with the solid shim.
Gary
Sounds like the correct procedure for a solid but I haven't used one yet. A friend just did this yesterday. He used an impact gun to draw in the bearings. He started out with about .010-.015" oversize compared to hte original crush sleeve. When he got to zero end play he still had no preload. He measured it with a inch/Lb wrench and it was about 2in/lbs. He then removed .002" in shims, applied 125 ft/lbs and the drag increased. He was working to about 15"/lbs the last I heard so that must be the way to do it. Let me know how you end up with the solid shim.
Gary
Thread Starter
Burning Brakes
Joined: Oct 2002
Posts: 1,040
Likes: 109
Re: rear-end question ?? (gtr1999)
thanks for the advice about the new vrs. the old bearings ,i will look at bearings to see if they NEED to be replaced,no need to replace if they are still serviceable.
thanks (gtr1999)
thanks (gtr1999)
Le Mans Master
Joined: Dec 2003
Posts: 5,727
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From: Fremont CA
Re: rear-end question ?? (1971corvette)
What do the "geniuses" who sold the solid spacer tell you to do? I don't understand why anyone outside of a drag racer would run one of these in their Vette. Think before you install a solid spacer, as the bearings wear (and they do wear!) you loose your pre-load on your bearings. I know many have said that a crush sleeve is bad but, I don't agree! The crush sleeve will compensate for bearing wear as time passes.
Thread Starter
Burning Brakes
Joined: Oct 2002
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Re: rear-end question ?? (Solid LT1)
(((The crush sleeve will compensate for bearing wear as time passes.)))
As my brain thinks,the bearings wear,the crush sleeve,OR the spacer gets looser.
Would you mind explaning how a crush sleeve ( compensates ) as bearings wear.
As much as my car gets driven,I don't believe I will have to much of a problem.
No worse then the bearings in the rest of the car,ie.
wheel bearings front,and rear,transmission bearings and or bushings, or solid lifters in the engine,everythings wears,just a matter of taking care of everything ,keeping clean oils and grease . :confused:
As my brain thinks,the bearings wear,the crush sleeve,OR the spacer gets looser.
Would you mind explaning how a crush sleeve ( compensates ) as bearings wear.
As much as my car gets driven,I don't believe I will have to much of a problem.
No worse then the bearings in the rest of the car,ie.
wheel bearings front,and rear,transmission bearings and or bushings, or solid lifters in the engine,everythings wears,just a matter of taking care of everything ,keeping clean oils and grease . :confused:
Tech Contributor
Joined: Aug 1999
Posts: 15,176
Likes: 3,990
From: Connecticut, USA
Re: rear-end question ?? (1971corvette)
Norval tested and found the crush sleeve will expand .002" when removed fromthe differential. Norval, I hope you don't mind me referencing you.
The reason I was going to use a solid and the reason my friend did was the ease of installation vs a crush sleeve. I have used a press,impact gun, large bar and they are a bear to start.I now start the crush in a press then transfer to the pinion. This works as long as the sleeve isn't crushed too much,just enough to finish with an impact gun. My friend likes the solid and will not use another crush sleeve. I think crush sleeves are reliable since they were used in hundreds of thousands differntials with millions of miles on them.
Gary
The reason I was going to use a solid and the reason my friend did was the ease of installation vs a crush sleeve. I have used a press,impact gun, large bar and they are a bear to start.I now start the crush in a press then transfer to the pinion. This works as long as the sleeve isn't crushed too much,just enough to finish with an impact gun. My friend likes the solid and will not use another crush sleeve. I think crush sleeves are reliable since they were used in hundreds of thousands differntials with millions of miles on them.
Gary
