MFJ

iTrader: (4)

Ok...so here is what happened. A friend of mine and myself changed the carrier and pinion bearings Thursday night after work. He is an ASE certified Master Tech (15 years all on Fords). I have 4 ASE's but I don't know **** about a rear end other than every time I touch one it breaks. This makes #4. This one worked perfectly and was so quiet after the bearing change until the pinion seal blew today. That's approximately 20 miles since the bearing change.

This is what I think happened and tell me if I'm wrong because I really need to know why a $5 seal is costing me more money

I installed the pinion seal with a seal installer. He installed the bearings on the pinion and set the pre-load. After he tightened the pinion nut you couldn't turn the pinion at all. So he loosened the nut and pulled the yoke off and the pinion back out. The rear race wasn't seated properly, although by sight, you couldn't tell. So the pinion was put back in and retorqued. I noticed the seal wasn't seated and he popped that side of the seal with a small hammer to seat it back in. This time you could turn the pinion but I think the damage was done before. When you put the pinion nut on and tighten it you in turn use the crush sleeve up.

By removing the pinion and not using another crush sleeve or shimming the difference could that cause the pinion seal to fail?
In all fairness the rearend was quieter than it has ever been. Bottom line is now I need a gear change. Under acceleration there is 0 noise but as soon as decel starts it whines bad.

flintwrench69

iTrader: (11)

Its not the seal causing the problems, sounds like the gear tooth contact pattern isnt set up right. Did you use contact paste & check the gear pattern? The seal might have got damaged from not installing it straight enough & got bent slightly. How did you torque the pinion nut? A new pinion nut & crush sleeve always, unless youre only changing the pinion seal. Proper pinion nut torque should take 25-35 in. lbs to turn, used bearings only 15-20 in. lbs. turning force. An impact gun works best tightening a lil at a time to achieve proper pinion nut torque & in. lb. torque wrench to check the turning force. From the sounds of it this wasnt done? Oh yeah & backlash with a dial indicator.

MFJ

iTrader: (4)

The pinion nut was torqued with an impact both times. When the pinion was installed we did use a new crush sleeve. He didn't after he took the pinion back out and re-installed it. He didn't check backlash or the gear pattern. Just installed bearings nothing else. It wasn't a new pinion or ring, it was the original one. Would that change just by changing the bearings? The seal was installed correctly when I did it. When the pinion was installed I believe that's what knocked the seal out. But it was knocked back in after that. I'm so pissed. Now the car will be down until this gets fixed. I just got it back running too.

I would rather work on a Yugo as I would a rear end.

SS SLP2

iTrader: (8)

" I " think here in ("The rear race wasn't seated properly, although by sight, you ...") is your problem, " I" think you should have used new sleeve, re shim and retork the pinoin AND reset the pattern and back lash
Johnny

MFJ

iTrader: (4)

I think the backlash and pattern should have been done too. I even asked that question and was told since it was just a bearing change it didn't require it. I also asked about the crush sleeve and was told he would just bring it back to wear he crushed it the first time. Like I said before I don't know **** about rear ends. I can't stay mad at him. He did screw it up for free

Honestly I don't have the money for a 9" or 12 bolt either so I'll have to put gears in this until I can save up for a complete rear end. POS GM rear ends.

01ssreda4

iTrader: (96)

What you're saying makes perfect sense. Sounds like he damaged the seal. Once the seal is in-place you cannot remove the pinion gear. The reason why is because the outer/smaller bearing is very tight on the pinion shaft. Hitting the gear back into the housing is fine, because the bearing hits the race. But re-inserting the pinion in causes that bearing to bump the inside of the seal which will tear it up. You must pull the seal if the pinion needs to come back out. Second, you don't setup crush sleeves with impact guns. Way too easy to miss your mark.

Big Al

iTrader: (1)

Never torque a pinion nut with a impact wrench. If you crush the crush sleeve you replace it. When you remove a pinion nut, even if it's only been on 10 seconds you throw it away. If he did what you said and used an impact to tighten the pinion nut to the point you couldn't turn the pinion he most likely damaged one of the pinion bearings. Take it apart BEFORE you drive it and find out what happened.

Al 95 Z28

flintwrench69

iTrader: (11)

Oh yea? Tell us why & what you would use, & what you use to hold the pinion in place? I have used an impact gun plenty of times gradually tightening the pinion nut in small increments until it has the proper amount of preload, usually 25-35 in. lb turning force.
I agree.
Yes, if you cant turn it by hand its def. overtightened, & most likely the whole reason why it makes noise. About just changing the bearings, yes usually you can get away with just doing that & not making any adjustments using the original gears, shims & carrier. Having the correct pinion bearing preload is very important & a good idea to check the tooth contact pattern in case it needs adjusted.

ctjohns

iTrader: (10)

I use a long 3/4" ratchet reduced to half inch socket. Also made a bar with two pins on it to catch the u joint strap holes. Then one can rest on the ground or whatever and you can have leverage to tighten the nut. Not to hard at all really...if you dont have the ability to figure that out, I wouldn't be messin with the rear to begin with. That being said, I have used an impact once or twice...can be very touchy and not advised for a rookie. Chuck

Big Al

iTrader: (1)

You can use an impact to start crushing the sleeve, but then you need to use a socket and breaker bar. I hold the U-Joint flange with a large pipe wrench. Read the manual, you can't loosen the pinion nut. You creep up on the proper torque and stop.

Al 95 Z28

flintwrench69

iTrader: (11)

Key words. Still is much easier to do with an impact than your method.
I know what the manual says & I always use an impact & it works great. Done lots of em that way.

shepss217

iTrader: (5)

wow wish i was ASE certified, how hard is it to get that? lol

flintwrench69

iTrader: (11)

Not hard at all. All ya gotta do is pass some tests.

MFJ

iTrader: (4)

Got new gears and bearings for the rear end. All ready to go again. This time I had someone who knows a lot about rear ends help me. Now I actually know why all the adjustments are made not just THAT they are made. It's quiet now, no clunking or popping and feels "tight". I can say the crush sleeve was never crushed after doing it this time. lol