001 from the shims then go with the thicker shims and tighten the nut some more. If you find yourself with not quite enough preload with one set of shims, but too much preload by removing. The 9 inch Ford uses 200 foot pounds of torque on the nut when using a solid spacer. I usually go at least 150 foot pounds when using a solid spacer, but you can add a few more inch pounds of preload by going as high as 200 foot pounds on the nut. You can make adjustments to the preload by tightening the nut more. I know a lot of people think that they can install a solid spacer and then tighten the nut as much as they want if they have to replace the seal or yoke. I know that a solid spacer is supposed to cure a lot of things, but don't be fooled into thinking that you can tighten the nut as much as you want and not change the preload. Just be sure that the seal is not dry and set the preload to the required spec.

Don't remove the seal to set your pinion bearing preload. It's a little different situation when using a solid pinion spacer, but still no need to remove the seal. You can not set the final pinion bearing preload without installing the seal first when using a crush spacer. Reinstall carrier with carrier shims exactly where they were, torque caps down to 60 ft-lbs.Ĭheck backlash hasn't changed (it shouldn't, but I'm paranoid so I'll check it anyway.) Install new pinion seal, torque down pinion nut to 125 ft-lbs and check pinion preload (open question - how much should I expect the pinion seal to add to the preload?) 10 in-lbs (using old bearings) without seal or carrier installed and using 125 ft-lbs of torque on the pinion nut (since I'm using the solid spacer and shims, and this is what they call out for pinion nut torque.) Use old pinion nut to set preload using new solid spacer and shims (might take a few tries) getting preload to approx. So, this is my plan as of right now (once the parts arrive):Ĭarefully disassemble and peek at it all looking for any signs of bad bearings or other ugliness. You're supposed to set the pinion preload without the seal or carrier installed, and then install the seal, new pinion nut and then the carrier and double check the backlash. I just realized - Doh! I do have to remove the pinion seal. I can always take it off and loctite it for more security. I didn't loctite the nut because it was dimpled, and I thought I would be tightening it much more. I didn't measure it, but as mentioned above, apparently the old pinion nut was not very tight either. So, my question is - is only 35-ft lbs of torque on the pinion nut ok? Going any more than 35 ft-lbs on the nut quickly gets the bearing preload increasing significantly. It only took 35 ft-lbs of torque to get back to around 15-20 in-lbs of preload on the pinion bearing (again, measured turning the pinion gear with an in-lb torque wrench and watching the breakaway load.) Backlash still measured the same, right around 0.0011. I then used the old thick washer and a new pinion nut and tightened down the nut. I then pulled out the old yoke, old pinion seal, cleaned things up, checked the front pinion bearing (it seems just fine), put in a new pinion seal, put on the new yoke after applying a little black RTV. It flew off - wasn't very tight apparently (this will be important.) Then, I used my impact gun to remove the old pinion nut.

It had about 0.0011 backlash (I've been told that is ok for a used gearset) and about 15-20 in-lbs of preload on the pinion bearing (measured by turning the pinion gear with an in-lb torque wrench and watching the breakaway load.) I just finally got around to replacing my leaky pinion yoke on my used 12-bolt with 4.10 gears (see thread here: ) and have a question about the pinion nut torque.īefore I replaced the yoke and put on a new nut, I measured the specs with a dial indicator and a in-lb torque wrench.

12 point breakaway bolts