triplethreat5188

well this weekend me and my buddy tackled the gear install and added a locker 5.13 i may add. Hes a car guy works runs his own shop but mostly works on tuner cars so the regear was new for him but not out of his league. Anyway he was just trusting me with the specs i had. After the install i took it around it drove nice i did about 15 miles and called it a night and let the gears cool. Next day i take it on the highway to get some miles on it. barely make it up to 65 it bucks and a crazy noise comming from the diff. Got it back to the shop and without pulling it apart we think its the pinion bearing. Here where i need some help Im seeing diffrent torque specs for the pinion nut all over the internet. We did it to 250 ft/lb off the specs i got off the project jk site. What do you guys think happend too much torque i also read not enough. Honestly i have no clue i ordered new bearings so would like to know what i should do it to next time

OJK12

When we do gears we tighten up the pinion nut until there is a slight drag on the end of the pinion when you spin it. That's how we have done every gear setup with no issues. Did you check the wear pattern and backlash before calling it good? How far did you drive it today? Gears call for 3 15 mile heat cycles. We setup a gear set on an XJ and the kid ran it 250 miles before letting it cool and the gears whined and made horrible noises.

triplethreat5188

made it about 6 miles. we have been trying to figure out what went wrong. After discussion we think that one of the guys who was trying to be helpful gave the guy who was installing the pinion the old crush washer. Think that could cause such ill effects. Wear and back lash were great backlash was .007 and wear right on

Offroad_Elements

Check out this info below, good luck

https://www.jk-forum.com/forums/jk-w...gearing-82262/

http://www2.dana.com/pdf/5717.PDF

& https://www.youtube.com/watch?v=dAqAqODmcj4"]https://www.youtube.com/watch?v=dAqAqODmcj4

OJK12

That could do it. Did you recheck the backlash after everything was done before installing the diff cover? If it was right then it should still be right because we have had to reuse the crush sleeve with guys not wanting to buy the full install kits with no issues. .07 is a good number we always shoot for .08. Seems like you guys know what your doing so I can't really say what went wrong. But check the pinion threads for the nut some of the gear companies have been over deforming the nuts and they strip the threads off the pinion.

Hoopskier

My thought is this is where you went wrong. I assuming you are working with a standard JK Dana 30. If you got new gears, you probably have a manual with generic install instructions and a spec chart. At least there was when I purchased my Yukon gears.

The pinion nut does not have a specific torque value, because it uses a crush sleeve. You should tighten the nut until it takes 6-8 (used bearings) or 12-15 (new bearings) Inch pounds of rotational torque . You need a beam style or dial indicator style torque wrench for this measurement. The "click" type of torque wrench doesn't work. Basically to do this, tightly the nut alittle, and re-check, repeat as needed. Important to not over tighten, crush the sleeve to much, and then you need a new sleeve.

Link to Yukon gears install book, has torque specs and generic install directions
http://www.yukongear.com/Downloads/M...structions.pdf