0pyders

iTrader: (3)

I was replacing the pinion seal. I forgot to count the threads or mark anything. I saw big gear head's post (and others doing the same thing) about tightening the nut, and read 150 ft. lbs. would work. when it came time to tighten the pinion nut my reading was a hair below 150 ft. lbs. My wrench read about 147, 148 and I figured that would be close enough (I could not physically tighten anymore laying under the car anyway). after I got the driveshaft on I couldn't spin it with both hands with the car in neutral and emergency brake off. I guess the nut is too tight. I see about 4 threads showing on the pinion shaft which looks like too much compared to other pictures I've seen of it. Probably need a new crush sleeve I guess.

Can someone help me with my problem. What would you do. I've done this twice now. I want to get it right. please.

Atilla the Fun

Torquing the pinion nut isn't about torque readings. I's about stopping frequently to feel how much pinion drag there is. The correct way to do this is with an inch-pounds beam-style torque wrench. Big Gear Head can give you the correct number to watch for. Until he posts that, take yours back apart, get a new pinion nut and a new crush sleeve, and stop tightening when you feel ANY drag at all. Then proceed to the specified resistance. Pay attention at 2:09.

big gear head

Sorry about that. I feel responsible for your problem. I guess that doesn't work in every situation. Most of the time that torque reading will work, but you might have a weaker crush spacer than normal, which caused it to crush more when you tightened the nut. The only really accurate way to do this is to remove the axles and differential so that you can measure the bearing preload when you tighten the nut. Most people don't want to go through all of that to change the pinion seal, so that's why I tested the amount of torque that could be applied to the nut before changing the bearing preload. 150 seemed to be a safe number, but not in your case.

The only way you are going to be able to fix this is to remove the axles and differential so that you can get the pinion out. I recommend getting a pinion kit with new pinion bearings, seal, crush spacer and nut so that you can set this up for the long run. Randy's Ring & Pinion sells a pinion kit with Timken bearings for less that the cost of the individual parts. Then you can set it up with about 19 inch pounds of preload and not worry about it again. If you try to do this with the used bearings then you will need about 7 to 10 inch pounds of preload, but you will probably find that you have at least one bearing that is bad or going bad.

You might want to use a solid spacer because you are working under the car and don't have the tools to apply a lot of torque to the nut. You can install the solid spacer and only apply about 125 to 150 foot pounds of torque to the nut instead of the 300 or so that is required for the crush spacer. It takes a little more time to get the solid spacer set up correctly because you have to shim it, but in the end it will still be easier on you to do it this way. Just be sure to use some red Loctite on the threads when you install the nut.

0pyders

iTrader: (3)

Thanks for the instructions big gear head. I needed it. I got the rear end all set up in my basement. Really I should have marked everything so I knew how far to turn it, I'm not blaming you for this. At least now I can easily replace the 26 year old bushings, shocks, etc..

Appreciate the video Atilla. Always easier than text.

0pyders

iTrader: (3)

hmm I started to remove the carrier today. I got the two caps off, the pin is out and the axles are slid out. I can't get the carrier to budge though. I was at it with a sledge hammer and a prybar and I don't even know if I moved it. Am i missing something? Anybody got any tips for this? Also after I removed the pin, 2 of those little (spider?) gears came out from trying to take the carrier out. I don't know which side came from which, did I screw myself?

jmd

iTrader: (4)

You can set the spider gears up later.

Put the bearing caps back on the same way you found them. Thread the cap bolts so they are threaded in but the outer bearing races have room to shift outwards. You're making sure the carrier doesn't fall to the floor since you're re-using parts.

If the pinion is still in, stick a bar through the pinion yoke inside the straps and turn the pinion slowly; it'll walk the carrier out. This works because the pinion has a mechanical leverage due to ratio. And you're using a long bar to turn the pinion.

Or if the pinion is out, hammer a punch from the other side against a cast section of the carrier until it loosens.

Those bearings are tight in there.

0pyders

iTrader: (3)

Thank you man, I'll get on it tomorrow.

Twin_Turbo

iTrader: (25)

and witness mark the nut and pinion with some paint!! this makes it so much easier to check i things have movd after you drive it for a little.

Also, IMO 150 lbs is way optimistic for a pre crushed crushs leeve, once they start crushing the required torque to crush further drops off RAPIDLY. I always use 100 pounds and then sneak up on it towards the mark I made (I know TS forgot this) and then check with a beam style tq wrench.

big gear head

Can you rock the differential back and forth or is it locked up? If you can not rotate the differential any then the pinion might have it bound up. I don't know how this could have happened, but it's possible. You should be able to pry the differential out, but they are usually in pretty tight. I use 2 pry bars. I hook them behind the ring gear bolts, one at the top and one at the bottom, and pry against the housing.

0pyders

iTrader: (3)

I can turn it no problem, but 1/2 way around I can hear a scraping noise with some resistance turning the yoke. I guess that's the bearings needing replacement.

Twin_Turbo

iTrader: (25)

make sure you didn't tweak the little shield and it's hitting the case

0pyders

iTrader: (3)

got the carrier and pinion gear out. Everything's cleaned up.

Looked at the 2 races and the outer bearing. No heat marks and couldn't get my nail to catch anything. Noticed "Timken" was wrote underneath the outer bearing. I guess that means its been taken out before? Anyway I didn't get a look at the Inner bearing, being without a separator and press. I was thinking about keeping the bearings/races and just using a new solid spacer and nut? Should I get the inner bearing pressed off the pinion to inspect too?

Let me know what you think.

I can get pictures for you guys if it helps. Thanks for your time.

Also if this helps: rear end worked great before I overtightened the nut. When I went to test it I heard a scraping sound, rolled the car a few feet then put it back to take out the rear end.

boy all this just from trying to change that pinion seal. what a tangled web i weave.

big gear head

If the bearings don't show signs of wear then you can use them again. The outer races will usually tell you if they are worn or not. No need to remove the inner bearing to inspect it. You can look at the rollers and see if there are any grooves or pits in them. The pinion bearings usually get the most wear because they turn about 3 times faster than the differential bearings. It's usually a good idea to replace them when you have the chance. If you use the old bearings again you need to be careful when you set the bearing preload. It's harder to set the preload on used bearings because you have to set it so light.

0pyders

iTrader: (3)

Ok I'll just replace them now while it's all apart.

0pyders

iTrader: (3)

Hey look here, I found out the yoke is rubbing on the top of this metal tab:


It runs into this before I can get any preload on the bearings. This is what that scraping noise was when it was in the car. Yoke is aftermarket. Can someone explain this? It's gotta be my fault somehow..

big gear head

So that is what locked it up when you tightened the nut? I would say that you can grind that tab off of the housing and probably fix the problem. If you have access to a lathe you could problaby cut the dust shield down to clear too.

0pyders

iTrader: (3)

yeah it's doing the same thing when it was in the car. Looks like your 150 ft lb. method won lol.

Twin_Turbo

iTrader: (25)

hello??? read much???

ASE doc

I just wanted to add, since I don't see where an actual spec was mentioned, I set pinion bearing preload on dry, new bearings at 25-35inlbs, then install the carrier and after setting gear lash, set assembly preload, again with new dry bearings, to 40-50 inlbs.

big gear head

Why dry bearings? I always use gear oil on them and set them to 19 to 22 inch pounds (pinion bearings). You can't accurately set the preload on the differential bearings because it's going to check different depending on the gear ratio. 40 incn pounds on a 4.10 gear is going to be MUCH more than 40 inch pounds on a 2.41 gear.

0pyders

iTrader: (3)

cmon lets not get rude. you were right. Since I've never worked on this before, I was a little confused about what you were talking about since the yoke is untweaked and the differential is open space except on the top (hidden) where that tab is. Now that I took it out I could see it.

TTOP350

iTrader: (8)

40 inch lbs is 40 inch lbs.. doesnt matter what gears are in the car.
The carrier should be out of the rear when checking the pinions rotating TQ.

What should have been done with the OPs org crush sleeve during the seal fix, is pull it out, mic it, then install a solid crush sleeve the same thickness of the crush sleeve. Then check the bearing preload with the inch lb tq wrench, add or remove shim as needed.
Thats the cool way, If its more of a stock rear I woulda put in a new crush sleeve and set it up.
You can also shim the org crush sleeve a bit and "recrush" it. There is a shim kit for that..
This isn't a procedure that you can "mark the nut" or "count the threads", Its a fairly easy deal tho if you follow the proper steps.

I have done 300 or so rear diff builds over the years..

big gear head

I wasn't talking about the pinion bearing preload. ASE doc said that he set the assembly preload to 40 to 50 inch pounds, which to me means that he is shimming the differential and checking the total bearing preload with the differential installed. As I said before, this will vary for different gear ratios. If you set the pinion bearing preload to 20 and then shim the differential for a total of 40 with a 4.10 gear, and you also set the pinion to 20 and the differential for a total of 40 with a 2.41 gear then the bearings with the 4.10 gear are going to be much tighter than the bearings in the 2.41 because of the difference in the leverage ratio between the two gears.

And I have owned and operated a rear end shop for the last 15 years.

ASE doc

That's absolutely correct. Thank you for clarifying that. I obviously have alot less experience with drivetrain than you do sir.

TTOP350

iTrader: (8)

I see what your saying, I'm not sure y anyone would check the bearing preload on the dif with the pinion in place?? (unless is getting a freshen and the total rotating tq was measured b4) As you said, that will give diff readings for different gears. That could get someone into trouble quickly.
I set them up kinda the same way you would setup a front wheel bearing..
The carrier bearing preload really needs to be checked without the pinion in there for the most accurate reading. Same with the pinion, no carrier in the housing.
As I'm sure you know, after someone does enough of them you get a feel for what's right.
I've been helping and building rears since I was 9-10. (damn, almost 32years)
It sure is nice working for yourself !!

big gear head

Yea, it's very hard to tell someone how tight is tight enough when there is no good way to actually measure it. Setting the preload on the differential is just something that you have to be able to feel. I judge it mostly by how hard it is to tap the shims into place. I get a feel for how tight the shims are and how hard it is to pull the differential out of the housing.

After 15 years I closed my rear end shop in June. Just too many things to do. I started building rear ends when I was 16, which was 31 years ago. The first one I did by myself was a 12 bolt in a '67 SS396 Chevelle. I wish I knew how many I have done.

SLEEPER 86

"After 15 years I closed my rear end shop in June."
Say it aint so BGH!
I was thinking about having you set up my 9bolt.
I am still here in Carlisle KY.

big gear head

Sorry, I had enough and decided to get out.

Brittany96

Hey big gear head, what if I don't know if I tightened the sleeve all the way or not. It's on a 95 GMC Sierra 1500. But when I have it tightened as much as I could which I'm 20 and weight 120 pounds so yeah. But I can't get the gears to turn easy at all, like if it's not tightened all the way. But I don't know this is my first time to ever do it. I just don't know.

big gear head

This would be best in a new thread instead of this one. Maybe a moderator will start a new thread for you.


I need to know what you are doing. If you are just replacing the yoke then there is one way to do it and if you are rebuilding the rear end or replacing the crush spacer then there is another way of doing it. Give me some more information so I can give you the right information.