Changing pinion seal 8 3/4

[tommymac]

How to?

[Shakey]

How to?

Did you search around this site for the different threads regarding this topic?  I think there might be one or two.  If not, the factory service manual should be helpful.

[RD]

1. jack up the car, place on jack stands (if you have a power impact) if not,
1. with car on ground, loosen pinion nut on yoke
2. remove yoke using a slide hammer and two of the yoke strap bolts OR put yoke straps back on and place a metal bar between both pull/jerk until yoke comes off  (i know this is not the most ideal way... but come on, who has not done this?)
3. remove pinion seal using seal puller or a flat tip (but making sure not to screw anything up (i.e banging on your pinion or smashing the pinion seal mount area)
4. place new pinion seal in area and by using the appropriate seal installer or two by fours, or a brass hammer, or something with mass that will hammer the seal in place without causing damage,... begin pressing the seal on while rotating blows.
5. grease the inner part of the seal with bearing grease and also grease the yoke where it will slide onto pinion
6. torque pinion nut down to 210 ft. lbs.


if anyone has a better way, or has noticed i stated something in error, please correct me

[Chatt69chgr]

Is the pinion preload totally independent of the yoke?  If so, I can see how you could remove ithe yoke, replace the seal, and replace the yoke without affecting the pinion preload.

[RD]

Is the pinion preload totally independent of the yoke?  If so, I can see how you could remove ithe yoke, replace the seal, and replace the yoke without affecting the pinion preload.

i am not sure.  that is a good question. i do not think the preload would be in question due to the pinion and gear being set and emplace already.  the fact that you are just removing the pinion nut and replacing it should not affect the situation i believe.  but, most definitely I could be wrong with my assumptions.

anyone know?

[firefighter3931]

[i am not sure.  that is a good question. i do not think the preload would be in question due to the pinion and gear being set and emplace already.  the fact that you are just removing the pinion nut and replacing it should not affect the situation i believe.  but, most definitely I could be wrong with my assumptions.

anyone know?

It depends on the carrier. 741/742 cases are pretty straight forward.....pull the yoke, swap in the new seal and re-torque to spec.

The 489 is a bit more challenging and requires removal of the centersection. The big issue is the crush sleeve which determines pinion pre-load and if you over/under tighten....the backlash will be off. So, as the yoke is being tightened....the backlash must be checked until the proper preload is achieved. There are solid spacers that are designed to eliminate the crush sleeve and most that tear apart a 489 case will use the solid spacer and shims to set pre-load and eliminate what is generally considered the biggest weakness of the 489 centersection.


Ron

[tommymac]

Everything went fine.Loosen,replace,tighten just as you said.742 not a problem.All new seals,new brakes,and now new SureTrac,cant wait to light Em up.

[RD]

Everything went fine.Loosen,replace,tighten just as you said.742 not a problem.All new seals,new brakes,and now new SureTrac,cant wait to light Em up.

outstanding... glad we could help out!  now go get some burnout pictures!! hehe

[tcurtis]

I realize that this is an ancient post, but my situation is such that I had a follow-up question and was hoping someone might have some advice.  In attempting to replace my pinion seal, all went well until trying to remove the yoke (nut was tough but eventually came off).  Using a slide hammer I couldn't budge the yoke.  If it moved it was imperceptible.  I used the two jaws clamped to the back of the tabs/shoulders and hammered away to no avail.  Since the seal isn't leaking very much I finally just re-assembled everything, topped off the fluid (didn't take much) and called it a day.  I was going to attempt to use a puller by threading the strap bolts back in but given that the force of the slide hammer was ineffective, and the bolts are so small I'm afraid of stripping them out or otherwise breaking them.  

By the way, I have a 741 rear.

Again, sorry to resurrect such an old post, but the directions were so straightforward it was easier to ask this way.

Thanks in advance for any help.

[c00nhunterjoe]

Its probably just some rust on the splines. Usually a few whacks with a hammer pops them off.

[W4ATL]

The instructions above were very helpful. My biggest issue was getting the pinion nut off. I spent two 2 days trying to get that sucker loose. I soaked it in WD-40, tried an impact wrench and a jack on the wrench and it just wouldn't budge.  Finally applied some heat, then used a jack with my wrench to finally get it to "crack". Still couldn't budge it by hand and I thought I broke something internal. I was about ready to put the driveshaft back on and take it somewhere that could lift it in the air and diagnose it when I thought to try the impact wrench one more time. Imaging my surprise when it started to come off! The rest of the job to remove the seal and install the new one only took 30 minutes. Drives like a champ and no leaks.