Pinion Seal Change procedure?

[JARichard]

Was just reading the service manual, What all needs to be done to change the pinion seal? DO I REALY HAVE TO PULL THE AXLES AND THE STEERING KNUCKLES?

TIA!

 

[ThomasLawrence]

DO I REALY HAVE TO PULL THE AXLES AND THE STEERING KNUCKLES?

Technically? Yes - because you're supposed to measure the rotational drag on the pinion, so that you can have the proper amount of preload on the bearing. Practically? I've changed a few out without removing anything but the driveshaft, but you need to have done a few "the right way" to get a feel for how tight the pinion nut should be.



Either way - be sure to clean the pinion threads and nut with some brake cleaner, and use Loctite to ensure the nut doesn't back off on you.



-Tom

 

[Tim]

You should use a new nut every time, those nuts are not reusable.



Honestly if this front axle uses a crush sleeve you should replace it, especially since the front axle spins all the time.

 

[SVenable]

You should use a new nut every time, those nuts are not reusable.



Honestly if this front axle uses a crush sleeve you should replace it, especially since the front axle spins all the time.

The statement is correct but...



Jeepers have this issue all the time, the axles are smaller, Dana 30's thru Dana 60's but the crush sleeves are a pain. We have had good success by installing a new pinion seal and then torquing the pinion nut to 165 ft-lbs. The crush sleeve on a Dana 30 starts to crush around 250 ft-lbs. I do not know what the torque is to start crushing the crush sleeve but it is probably around 450 ft-lbs. If you torque the nut to 200 ft-lbs it would probably be fine.

 

[GDouglas]

I haven't done a pinion seal on any of the newer trucks yet, but I have changed out a lot of pinion seals on a bunch of differentials in my many years as a mechanic. First the facts. You are only replacing the just the seal, not the bearings. When the seal is replaced, you want to duplicate the exact preload that your existing pinion bearings had before you took the nut and yoke off in order to replace the seal. The way I do this is to make some witness marks before I remove the pinion nut. Select a corner of the pinion nut to make a center punch mark on and then directly in line with the same corner of the nut, center punch a mark on the end of the pinion shaft just inside the minor diameter of the threads. I usually make a third mark on the yoke itself too, so that I am able to reassemble everything back in their original positions. After you replace the seal, all you have to do is run the pinion nut down until your marks line up. You will at this point have exactly the same pinion bearing preload that you started with before seal replacement. Don't forget to clean the threads of your pinion nut and shaft and use blue loctite to prevent the nut from loosening.



I have used this method for years with great sucess.