I think you will have to remove the pinion nut and flange that the driveshaft bolts too also. If thats the case you will have to take the posi unit out to aviod damaging your ring and pinion. Thats the way I remember it anyways, its been a while.

 

Yep, you pretty much SHOULD remove the axles, carrier, etc. You'll need a new crush sleeve on the pinion, so you pretty much have to pull it all apart to do it.

 

alright thanks guys

 

I think you will have to take it all apart. To get the seal off, you will have to remove the flange which is larger than the seal. To get the flange off you will have to remove the pinion nut. Once you remove the pinion nut, you will need a new crush sleeve and an inch pound torque wrench to set the preload. In order to put the new crush sleeve on, you have to remove the front pinion bearing. I think that once the seal is out, the slinger and bearing itself will come out, and then you can slide in the new crush sleeve. I am kinda going from memory here so it may not be 100%. If you can't get the crush sleeve out that way, you will have to pull the carrier. You will likely have to pull the cover to allow the diff fluid to drain since once you pull the seal only some of the fluid will come out - best to do a complete change rather than 1/2 old and 1/2 new. If you have to pull the carrier, you should check your backlash, to make sure you have it all back together.

I think that about covers it - I have done a complete rear end rebuild, but never just a seal replacement, but I will have to do it since mine is leaking. The one I got in the FRPP rebuild kit is hopeless. I just got and OEM part and it is much better - you can see it has a seal around the outer edge to stop the way I think mine is leaking at the moment. Don't forget to lubricate the seal around the pinion to stop it burning up on start up.

 

To do it poperly I would say take the rear end apart only for the reason you are backing off the pressure on the crush ring, if you don't take it apart it will be hard to set the pinion force back to what it is suppose to be when you reinstall, could be a bit risky.

If you replace the seal then you will need a crush ring as well and make sure it is torqued to the right spec ( 8-14 in lbs to turn the pinion) it will take allot of force torque the crush ring though.

You can read up here http://www.corral.net/tech/drivetrain/gears.html

 

I wouldn't trust the article on the Corral...

You 'could' do it w/o removing the diff, pinion, etc., but you'll have to be real careful when toqueing the pinion nut. You won't be able to establish a benchmark or reference pinion bearing preload w/o disassembly, so it's a bit risky. If you're gamey, the minimum nut torque should be 140 lb-ft; hit that and you're good to go (it'll take more than 140 to crush the sleeve; just sneak up on it slowly, feeling the 'system' preload as you go to detect any changes; if it changes, take it apart)...

-BUT-, if something's off, I'm not liable...

 

I wouldn't trust the article on the Corral...

You 'could' do it w/o removing the diff, pinion, etc., but you'll have to be real careful when toqueing the pinion nut. You won't be able to establish a benchmark or reference pinion bearing preload w/o disassembly, so it's a bit risky. If you're gamey, the minimum nut torque should be 140 lb-ft; hit that and you're good to go (it'll take more than 140 to crush the sleeve; just sneak up on it slowly, feeling the 'system' preload as you go to detect any changes; if it changes, take it apart)...

-BUT-, if something's off, I'm not liable...

That's right - I had forgotten! You won't be able to get the right preload with the carrier in place! You will have to pull the whole thing apart.

Chris - (I'm assuming this is Chris Neighbors - as in "for the want of a gear") can you put it all back together and not worry about backlash, or is key to check that as well and do the gear marking compound thing, considering nothing is getting changed. I will probably check it just for kicks anyway, but was wondering if that was routinely done, say with trac loc rebuilds etc.

 

Cobra,

If you're careful, you can put it back together w/o affecting the pinion depth and backlash. As long as you're carfeful with the nut torque, it should be fine. I had to do one this way for sure (on my car, some time ago; I won't experiment w/others stuff, too much! ), w/o a hitch...

When I do a gear instal from scratch, I check bearing preload a few times, easch direction, backlash in about five or six spots, and run-out two revolutions. After all that, I still use marking compound to give me a good visual...

If I do a T-lokl rebuild (which I always pull the diff; easier on an old man like me!), I don't check anythig when I'm done, -as long as- I keep the shims in order (and you should anyway). R&R'ing the carrier won't change any settings as long as you keep the sides in order...

Boy, I need to have Chris, Bob, or somebody update the article, LOL! It's been a few years, and more details have been added. I guess I need to redo it myself and resubmit, LOL!

Chris

 

Cody...

You do not have to dissassemble the whole rear diff assembly to replace a pinion seal.

I have done probably hundreds by now and never once had to remove the carrier, axles, any of that stuff.

Getting the preload correct is just a matter of being careful when you reinstall the pinion nut. Pinion depth and backlash will be unaffected by anything you do with the pinion nut. The only thing that will affect is pinion bearing preload.

Also make sure you put some sealer behind the flange of the nut, or you can have fluid leak out from the splines and it can appear like a pinion seal leaking.

 

SIG is correct, I didn't do it to my car because i wasn't comfortable so I took it to ford and they got the pinion seal on in about 35 min.

 

Cool thanks mike, thats way easier, I appreciate the help!!!
Cody

 

Ysigonzo, how do you set the correct preload on the pinion with the carrier in place? Will that not artificially increase the preload reading resulting in the pinion nut not being torqued down far enough. I need to replace my seal and would rather not pull the carrier, but I thought that the preload needs to be set with the carrier and axles out so that it will not create additional preload drag.

Thanks

 

Any thoughts on this Ysigonzo???

 

Put your nut back on and tighten it until you hit a ton of resistance. Then you know you are up against the crush sleeve.

It is done by feel.

As anyone knows that has set up a rear end, the crush sleeve doesnt just collapse... it is quite the bitch to preload sometimes. SO by tightening the pinion nut to where you cant tighten it no more, you have reset preload.

How many rears have you set up cobradvm? How many pinion seals have you replaced? How many swaps have you done?

I am guessing not very many, or you would already know this.

Like I said I have done hundreds by now, all with the same technique. Ask any of my numerous customers if they had any further issues....

 

I have only changed the gears in my own car from 3.08s to 3.73s so I defer to your experience. From what I read before I did my gears, the amount of preload on the pinion bearing was critical. If you have new gears the preload should be 16-29 in-lbs, and for old bearings 8-14 in-lbs. The amount of torque required to get the crush sleeve to collapse is over 140 ft-lbs - obviously quite a bit.
Clearly you have done this enough that you can tell simply by how it feels as you torque down the pinion nut. I would imagine that if you haven't done this hundreds of times before, and you simply torque it down "to where you cant tighten it no more" the chances are, the preload won't be correct and bearings will fail.
I don't know how much drag the carrier and axles will place on the pinion bearing, but I bet its enough that the reading on the torque wrench will be off by a significant amount. That's all.

Sorry if I got your dander up, it wasn't intentional. You have probably forgotten more than I'll ever know. I'm just some dumb country bumpkin trying figure this stuff out

 

wow, all i do is grab an inch lbs wrench and check drag before i unload the nut, unload the nut, take the flange off, tap lighty around the entire seal with a screwdriver, pop it out, clean the inside with a scotch pad, wait until oil stops coming out, clean bore with carb cleaner and put new seal in with a pinion seal driver. i install them dry if they have the lip of sealant around them from ford, permatex black if they don't. install flange, use a 1/2 impact, sleeve is already crushed, creep up until drag is where it was when you started, top off with oil, road test and recheck and ship it. pays 1.4 get it done in .5. no comebacks.

 

I can tell Noel has done this before...

cobra, no offense taken. The way I do it is a very reliable way, just trying to reiterate that.

 

yes i have done them hundreds of times. But, from that post you would think I HAVEN'T TYPED ANYTHING IN MY ENTIRE LIFE, but, thats fixed now. . i forgot to add i do also put a little oil on the inside of the seal just like you would with a rear main, just to keep things happy.

 

Cody...

You do not have to dissassemble the whole rear diff assembly to replace a pinion seal.

I have done probably hundreds by now and never once had to remove the carrier, axles, any of that stuff.

Getting the preload correct is just a matter of being careful when you reinstall the pinion nut. Pinion depth and backlash will be unaffected by anything you do with the pinion nut. The only thing that will affect is pinion bearing preload.

Also make sure you put some sealer behind the flange of the nut, or you can have fluid leak out from the splines and it can appear like a pinion seal leaking.

this is my experience also I have done it many times and just take the yoke off and pry the seal out and tighten the nut back on with air power and w-d 40, the book calles for [I think] 200 ft pounds of tourqe so i let it have it, also air tool takes it off easy you dont have to deal with the yoke turning, but E brake would probably hold it, I have done it mabe 3-5 times like this and NEVER A PROBLEM