Replacing pinion seal on 8.75 rear end

[lochenjons]

Sorry I should have mentioned it’s a 742 case. Right now the pinion nut is very snug. Yoke spins freely with a very slight amount of resistance. No clunks or weird feels like grinding or anything when I turn it. Same yoke same everything

 

[Fran Blacker]

Man, after doing this stuff for over 30 years, I've never ever worried about hitting that damn high torque figure! IF you have the 89 case, mark the nut and get it back to where it was or you'll take the chance of crushing the sleeve a bit more and making the bearings too tight. On the others, do the same and do a 'feel' test to see if it still turns like it did before. Main thing is that you do not want to be too loose or too tight but on the 89, if you end up too tight, the crush sleeve probably got crushed some more and then you need to either shim it or start over and yes, you can shim it. If that happens, shimming it is a crutch but it works. That high torque stuff is for new set ups with new bearings but even then, I don't even try to hit it on the 41's and 42's and all 89's I do gets the crush sleeve eliminator kit...ie, solid spacer and then use shims to set preload. Just my opinion from an old fart that's been there done that.

Cranky its a 742.

 

[Cranky]

Cranky its a 742.

I gave a general reply to all 3 but to me, the 42 is easy. Even if you tighten the nut to 7000 ft lbs, it shouldn't make the bearings too tight....well, maybe that much will LOL. I have no idea why the factory specs quote such a high torque reading but they do. I use a good impact wrench and use a dab a red Loc-tite and have never had a problem. I estimate my impact produces close to 180 ft lbs based on what it is and what it's supposed to put out.

 

[lochenjons]

I gave a general reply to all 3 but to me, the 42 is easy. Even if you tighten the nut to 7000 ft lbs, it shouldn't make the bearings too tight....well, maybe that much will LOL. I have no idea why the factory specs quote such a high torque reading but they do. I use a good impact wrench and use a dab a red Loc-tite and have never had a problem. I estimate my impact produces close to 180 ft lbs based on what it is and what it's supposed to put out.

I’m happy with that method, it makes sense to me. Pretty much what I’ve done all my years of wrenching. One last question, how much resistance should be on the yoke when I turn it? Should it be the same as if the nut was loose?

 

[khryslerkid]

Sorry I should have mentioned it’s a 742 case. Right now the pinion nut is very snug. Yoke spins freely with a very slight amount of resistance. No clunks or weird feels like grinding or anything when I turn it. Same yoke same everything

Try to see if there is any markings on the seal surface from the yoke. Maybe the outer part of the seal is interfering with the yoke?

How tight is the seal on the speedy sleeve? Did you try the seal on there before installing the seal?

Just spitballing. Doesn't make sense that it's getting tight on you.

 

[khryslerkid]

One last question, how much resistance should be on the yoke when I turn it? Should it be the same as if the nut was loose?

It's in inch pounds, like no more than 10. I'd have to look it up. In all actuality it should be the same as it was before you took it apart.

 

[lochenjons]

The seal fits great on the redi sleeve. I’m going to throw some loctite on there and tighten it down and see what happens. It’s goinf back up on jack stands after the “shakedown”

 

[5.7 hemi]

You can’t measure the rotational torque with the chunk in the housing. It needs to out and held with a vise or equivalent. Then you take your rotational torque wrench and turn it. Your looking for 12-20 on used bearings and 10-15 on new bearings. I know those aren’t the figures that are listed, but that’s what I like and it hasn’t failed me. Also if you mark the ring gear and use your hand, wooden stick, etc., to put some resistance on it, you will see how well your pattern looks. Much better this way as your seeing an actual pattern with a load on the gears.

 

[khryslerkid]

The seal fits great on the redi sleeve. I’m going to throw some loctite on there and tighten it down and see what happens. It’s goinf back up on jack stands after the “shakedown”

Are your drums still on the axels?

You can’t measure the rotational torque with the chunk in the housing. It needs to out and held with a vise or equivalent. Then you take your rotational torque wrench and turn it. Your looking for 12-20 on used bearings and 10-15 on new bearings. I know those aren’t the figures that are listed, but that’s what I like and it hasn’t failed me. Also if you mark the ring gear and use your hand, wooden stick, etc., to put some resistance on it, you will see how well your pattern looks. Much better this way as your seeing an actual pattern with a load on the gears.

I was looking through the FSM and the numbers were similar but it was without any ring gear or seal in the housing, just when checking the pinion preload. In the OPs case, that's probably not going to help any.

 

[5.7 hemi]

I prefer to check rotational torque with it complete. That way you get an accurate reading of what it takes to turn the ring/pinion.

 

[lochenjons]

Are your drums still on the axels?

No I installed a rear disc conversion, before I put the yoke back on everything rotated smoothly. No dragging brakes

 

[Fran Blacker]

You can’t measure the rotational torque with the chunk in the housing. It needs to out and held with a vise or equivalent. Then you take your rotational torque wrench and turn it. Your looking for 12-20 on used bearings and 10-15 on new bearings. I know those aren’t the figures that are listed, but that’s what I like and it hasn’t failed me. Also if you mark the ring gear and use your hand, wooden stick, etc., to put some resistance on it, you will see how well your pattern looks. Much better this way as your seeing an actual pattern with a load on the gears.

Thought new bearings got 20 in lbs because they loosen up after break in. Used bearing get the lower reading?
You can't measure pinion bearing resistance with ring gear in place.

 

[5.7 hemi]

Dammit! I had that backwards! Long day working on this Belvedere.

But I do measure rotational torque with it completely assembled.

 

[Cranky]

Dammit! I had that backwards! Long day working on this Belvedere.

But I do measure rotational torque with it completely assembled.

I know that feeling lol. I was super tired from doing stuff all week long and am still dragging butt but got to get on the stick anyways!

 

[Cranky]

I’m happy with that method, it makes sense to me. Pretty much what I’ve done all my years of wrenching. One last question, how much resistance should be on the yoke when I turn it? Should it be the same as if the nut was loose?

No, not really unless the front bearing is tight on the pinion shaft and that happens. I just took the Dana 70 in my truck apart and had to hammer the pinion out so that told me the bearing was pretty snug on it....

 

[lochenjons]

Well I'm at a loss of what to do, I put some loctite on it last night and got it reasonably snug. Everything seems solid

 

[Cranky]

Well I'm at a loss of what to do, I put some loctite on it last night and got it reasonably snug. Everything seems solid

You're saying the yoke won't turn??

 

[lochenjons]

You're saying the yoke won't turn??

The yoke turns now, but its not at 240'lbs

 

[Cranky]

The yoke turns now, but its not at 240'lbs

Did it have more torque on it and it wouldn't?

 

[5.7 hemi]

You don’t by chance have the e-brake on?