I’m sure we’re all going to run into this if you beat up your rigs as much as I think (hope). It’s important to fix as soon as possible to avoid bearing damage and as we all know where oil leaks out water gets in, and water is a diffs worst enemy. So let’s make this quick..
Chock your wheels front and back as the weight of the vehicle should be enough to stop the pinion from spinning while removing the nut. We will get to a clever trick if it does happen to be on there really tight.
Remove your driveshaft, two ubolt straps on each end. Carefull not to drop it on your head, it’s heavy. Note this is a great time to clean off any built up crap on the shaft and thoroughly check your u-joints.
Take a punch and mark the nut and the shaft so you can realign them during reinstallation. This will keep the pre load the same and not wreck the crush sleeve.
You will need a 1-1/8 socket and the biggest breaker bar or impact gun you can fit under here. Go ahead and remove the nut. As I mentioned earlier if your lacking a powerful impact gun here is an alternate method that almost always works.
Take the strongest ratchet you own and place it as shown above, unchock your rear wheels and slowly reverse the vehicle. You will feel the tire grab when the ratchet makes contact with the leaf spring, give it a touch of gas and it should break the nut free. Do not move to far there after! As you now have no pre load on the bearings.
Remove the nut and washer. Then remove the yoke, it may need some love taps to pop it off. Once again make sure it doesn’t fly off and hit your face, it’s heavy.
A wood chisel is your best friend here, a flat head will do but may take a little more time. Take your chisel or whatever and place it in the outer lip (above) and hit it with a hammer to puncture it through. Fluid might pour out so have a catch ready. Work your way around a little repeating the process, picture old school can opener action. Once you’ve gotten about a quarter to half of the way around pry it out, it should be very easy by this point.
Clean out the area as best as possible for the new seal.
If you have any put a thin layer of RTV or silicone around the outer edge of your new seal to help it do it’s job. Note there are rubber, silicone and viton seals available. This being the viton, we will see how it holds up in the long run in comparison to the others.
Gently tap around the whole circumference of the seal as not to bend the outer lip until it is flush with the housing.
Re assemble, tap your yoke back on, place washer then torque the nut to (160-260ft) as per FSM with plenty of lock tight if re using the original nut. I start on the lowest torque setting (160ft) and see how close your punch marks are apart, then just tighten until your marks align. Edit- I should mention the. FSM calls for a new nut and washer , which makes realignment more complicated. Lock tight should hold up but use your own discretion. Washer Quadratec PN# 52423_02 Nut Quadratec. PN#52449_0200.