new pinion bearing's preload

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Mar 23, 2002 | 08:33 PM

acogoff

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new pinion bearing's preload

I need advice from experienced ring and pinion guys. I find various preload recomendations for new pinion bearings from 10 to 15 in. lb all the way up to 29 in lbs. Am I wrong in thinking that the low settings are from people who are not working on their own vehicle and just don't want to have people coming back with burned out pinion bearings because they didn't have a clue how to run in a new ring and pinion. Am I wrong in maybe setting preload at around 20- 22 and baby the rear end for a while? It's a 9 inch ford oem rear end.
1980 F-100

Mar 23, 2002 | 10:17 PM

Art

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new pinion bearing's preload

[updated:LAST EDITED ON 23-Mar-02 AT 11:25 PM (EST)]As a rule of thumb, I have always read (and used) 10-15 in-lb for used bearings and 25-30 in-lb for new bearings. Never had one come back...knock on wood...

Extremely important is the crush sleeve - it must maintain the bearing setting without crushing more later on. If it crushes more later, the pinion bearings will run too tight and fail. I always use Loctite 272 on the pinion nut of axles that use a crush sleeve.

I prefer shimmed pinion bearing preloads like my Dana's and 8-3/4's use.

One more thing - I think most ring & pinion failures are caused by bearing failure, incorrect pinion depth setting, and incorrect backlash. Properly set-up gears DO NOT make noise.

Art
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Mar 24, 2002 | 12:06 PM

acogoff

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new pinion bearing's preload

Thanks for the info. Although I don't understand how a crush washer could crush more as I had to use a 3/4 breaker with a 3ft pipe on it with yoke in the vice to get the crush washer crushed enough to get my 20 in lbs preload,I'll take your word for it. I used blue loctite on pinion nut threads and got it all together this morning and took her for a easy 25 mph 2 mile run . so far so good. tommorrow I'll ease to work 15 miles on back roads and hopefully then it will be ready for more speed. Carrier bearing failure was cause of rebuild. Thanks again.
acogoff 1980 F-100 300 six 4speed

Mar 25, 2002 | 07:35 PM

FortyFords

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new pinion bearing's preload

yes crush sleeves are a pain in the butt to get right
the 9" is the easy to work on compared to the newer diff's
I hate the shims
Wish they had stayed with side adjusters.
Just my$ .02

Rich

Ford Trucks Built Tough!
not with rocks
Watch out "X" Mayor of Truckville

Mar 28, 2002 | 11:39 AM

AZ4x4f150

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new pinion bearing's preload

[updated:LAST EDITED ON 28-Mar-02 AT 12:42 PM (EST)]after i got my crush collar to the proper size i went to a machine shop and gave him the crush collar and asked him to make me a stainless steel bushing exactly the size of the crush collar he said no problem and made it now i don't have to deal with the crush collars anymore just install the stainless steel bushing and do the proper preload and it is all said and done never had a problem in 6 years and 4 R&R&OH of the same 9"along with new pinion bearings and carrier bearings and the bushing only cost me $20.00 for the machinist to make I know with used bearings Ford spec is 16-24 in/lbs as for new bearings I go with 24-30 in/lbs never had one come back yet also ,,,knock on wood

May 3, 2002 | 07:46 PM

toyshop

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new pinion bearing's preload

Have used 20 inch lbs on many a gearset. Again, no failures, knock wood.

May 11, 2002 | 10:57 PM

stingray

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new pinion bearing's preload

I learned a new trick to handling those crush spacers. Instead of all that sweatin' and swearin', I just throw them on the lapping table a few minutes at a time till it starts gettin' close then lap it by hand to finish it up. Sure beats a cheater-pipe on my old arbor press.