how do i replace a rear differential pinion seal

I've never done this before but I dont think it should be that hard.
I changed the gear oil a little more than a month ago and i wash the underside of the truck everytime it goes off road. i noticed the oil on the drive this morning and want to fix it ASAP. how long do you think this could take? I start a new job tomorrow and will be driving almost 70 miles per day.

 

Do you think Advanced would have an SST tool for me to borrow?
What is an SST tool exactly?
Is there any thing i can use as a substitute for an SST tool?

 

I replaced mine a couple of weeks ago. Granted this is on a 2nd gen but it should be very similar.

It's an easy job if you have the right tools. Thankfully I had just bought an air compressor and an impact wrench; which I had to use to get the driveshaft unbolted from the flange and to remove the pinion nut. Suckers were on very tight and the pinion nut is staked. Plus with the impact wrench I didn't have to worry about trying to keep the flange/wheels from rotating with the nut.

I used a 6'' gear puller to pull the flange off. From that point you have to pry the seal out, give the new seal a thin coat of high temp grease, and reseat the new seal. You're going to need something the approximate diameter of the seal in order to seat it. It's a tight fit and you gotta be careful not to damage the seal.

I'd recommend you pick up a Hayne's repair manual. It goes through repairs like this in simple steps with pictures. Mine is covered in grease and is like a Bible for the garage.

I'd also highly recommend you check that your rear differential breather is not clogged. That is likely the cause of the leak (if it can't breath through the breather, it will find the next easiest place to vent hot air and that's going to be the pinion seal.

 

Dude, thanks for the info! I just hate the thought of someone working on my truck, let alone getting payed to do it