[94bronco]

I just replaced the rear axle seals, bearings, fluid etc. trying to diagnose a squeal I was having. Turns out it was the double cardion joint, no surprise, in the DS. Then I got new tires 33.12.5 15 BFG AT’s and now after all that I’m hearing what sounds like the backlash setting is wrong in the rear while coasting from 20 mph and under, there is a whining sound but only while coasting. Could this be the tires? I never heard this sound before but these tires are much quieter than the others. The tires are siped and I’ve never had a pair siped before so I’m not sure. I’m going to check the diff fluid this weekend, shouldn’t be low I just replaced it less than a month ago and it has no leaks but I’m thinking that maybe while I was cleaning out the axle tubes from the debris from the bad bearings maybe they didn’t get filled until the bko was driving and now the fluid is low. Any thoughts outside of pulling the diff cover and checking the backlash on the ring gear?

The correct backlash is between .006 and .010 correct?

Thanks.
:beer

 

[muddybronco]

whining noise and 8.8? better check that pinion nut! :duh

 

[94bronco]

whining noise and 8.8? better check that pinion nut! :duh

220 foot pounds correct.

 

[Blaze]

:stupid Been there, done that...got the t-shirt, but had to sell it to buy new gears! :toothless

 

[Mrit]

No, not correct. It takes a MINIMUM of 200 lb-ft to BEGIN compressing the crush collar, but that's not the spec for the pinion nut. You tighten it until you get the correct rotating torque on the pinion bearings, measured in INCH-pounds. Read this and this.

Your first link dosen't work.

 

[94bronco]

OK this more than likely my fault but it's been working fine for the last 2 years. I originaly setup the rear, had them checked by the shop that setup the front and they only changed the backlash in the rear by .002, not the pinion nut preload.

Question is can I just tighten the nut to the specs or do I have to replace the crush sleave. Only problem with just tightening the nut is you have no idea the pinion bearing preload.

Or do I just take it to a shop.

Thanks