RB83L69,

I don't know you well but I spent the last two hours reading your posts on stuff, and, you know your stuff when it comes to rears.

I had a 9bolt, ripped it. Built a 10 bolt.

Zexel carrier
3.73 richmonds
new bearings pressed on carrier
new axle bearings, seals, etc.

Shimmed the rear end. Drove it. Carrier loosened up a little. added a shim to the left side. Spread pattern isn't bad. When you hold the ring gear, and turn the drive shaft its got like maybe
.010 of play which I was told was "just right".

Anyway.. I checked the pinion. Depth from center of the axle is right around what it should be (2.31 is what it shoudl be, its damn close if anything). I think I screwed up on the whole sleeve thing.

Now, I put the seal in, put the crush sleeve in, put the yoke on, and tightened with the impact gun. I don't know how to cehck payload. I dont have the tool for that..

If I buy a crush sleeve eliminator, how do i put this back together?


Anyway, as far as driving goes. at around 80ish mph (110 on my speedo, which is now off) the vibration is SOOOO bad, I can't
hold the shifter.. RPM = 2200, in 4th. So driveshaft was 2200.


Comments??

-- Joe

 

not sure about how to fix the vib, but i know that if you disconnect the driveshaft from the rear end and turn it 1/2 a revolution(clock wise) the vib will either go away or you'll feel less of it. I know that this solution is not fixing the problem but it helps to minimize the situation.

 

Here's how to use the sleeve/eliminator thing.

Since you've had it apart, you know how it goes together.... think of those pinion bearings. Obviously the 2 outer races are in a fixed location, which is dependent on the way the housing is machined; the inconsistency in the machining is what the crush sleeve is designed to accommodate.

The shim behind the pinion head bearing sets how far into the housing the pinion extends. For whatever reason, the housing machining of the head bearing inner race, which ultimately determines where the pinion sits, is fairly repeatable; nearly all stock pinions have a .035" shim in them, and nearly all stock-design gears can go back with that same shim; it rarely needs to be more than a couple of thousandths different from that even when carefully set up for perfection.

Once you get the pinion depth setting right, the next thing you have to do, is tighten the nut down against the tail bearing, which mashes it inward along the pinion shaft, crushing the sleeve. There's nothing keeping the bearing from sliding into the housing along the shaft, except for the sleeve. As you tighten the nut and crush the sleeve, the tail bearing moves inward, decreasing the distance between its cone and its outer race. Eventually it gets to a point where there's no slack left between them. You're supposed to continue tightening past that "zero-lash" point, further crushing the sleeve, until it takes about 20 inch-pounds to turn the pinion in its bearings. At that point, the only thing keeping the bearing from tightening further, is the crush sleeve; and the only things keeping it from loosening, are the nut's lock feature, and the "crush" on the sleeve. Not particularly reliable if you want to exceed the stock-design power transmission load on the rear.

If you could measure the length of the crush sleeve at that point, you could then make a spacer of that exact length, replace the crush sleeve with it, and tighten the nut until it screams for mercy, instead of having to delicately avoid over-tightening it. Then you'd never have to worry about the crush sleeve getting crushed slightly more by use, which will remove one of the things keeping the nut in place, which will allow it to back off, which of course will kill the whole thing.

That's what the crush sleeve elimintator does.... it allows you to select shims, decreasing them in small steps, until the correct bearing preload is acheived; at which point you can murder the nut onto the pinion, and never have to worry about it coming off, because it's tightened down onto a solid column of metal that can't change its thickness.

So: to put in the crush sleeve eliminator, you'll need to remove the carrier; remove the pinion and the seal from the housing, and the tail bearing from the pinion in the process; take out the crush sleeve, and replace it with the non-crush sleeve and stack of shims, and see how much play it has; then take it apart and remove an educated guess's worth of shims, and check the play again; etc., until all the play is removed, and continue removing shim until it takes about 2 ft-lbs to turn the pinion when it's fully assembled.

The kit comes with about 4 or 5 shims, that are something like .015", .018", .021", .024", & .027"; so for instance if you discover that with the .015", .024" and .027" in there it takes 1 ft-lb of torque to turn the pinion, you'd take it apart and put it back together with the .015", .021", & ,027", and check the torque; and keep doing that until you get to 20-25 inch-lbs (about 2 ft-lbs) of torque. Honing the inside of the tail bearing cone with a brake cyl hone until it slides more or less freely onto and off of the pinion will make it much easier to take apart and put back together.

Hopefully your bearings aren't damaged from being either grossly too tight or too loose. If you have vibes, then they're probably loose right now, and they're probably OK, but I'd sure check them carefully (especially the tail bearing). You might want to just go ahead and get a new tail bearing anyway, since it's easy and cheap.

It wouldn't be a bad idea at all to replace the pinion yoke. Stock ones don't take too kindly to lots of pounding and beating, and if it's bent, your drive shaft will be permanently off-center to the pinion. http://www.drivetrainspecialists.com...=28&cat=GM+7.5 You need the one for the 3147X U-joint.

Once you get that where all of that is known to be right, let us know if you have vibes, and we'll go from there on identifying them.

Good luck!

 

i'd leave the impact wrench in the tool box too, just use a socket and handle to tighten the pinion nut

 

RB83L69,

Thank you for the response!

OK, and now for confusion, and me second guessing my assembly.

The pinion has 2 shims which make up .035 right now, then a pressed bearing. Which bearing is this? Then this goes into the housing, where there is a pressed race.

Now the external assembly is where I'm confused. What is the order of the parts? Do you have a picture for reference?

Even worsely confused now. Tail bearing, now thats the one on the outside right? What does honing it out do? This slides easily over the pinion as is, doesn't it?


Assuming you help me understand the correct order and assembly now, especially pertainign to that "tail bearing" and the honing, I would basicly then put the spacer in, then shim's between it and the bearing, and wack it with the gun until the nut stops turning. Then check preload, and remove shims until its 2lbs..?

When checking preload, this is just with the pinion right, I.e, remove the carrier? Or can I leave the carrier/axles in?

Thanks!!!!!!!!

-- Joe

 

That's the head bearing. Think of the pinion as looking like a tadpole or something.

Honing out that smaller bearing allows the pinion to slip in and out of it without having to beat it out. That way you can put it together, tighten the nut and test it, and take it back apart, multiple times.

Your description of what you think you'd do is essentially correct. I wouldn't use the gun though; I have a tool that I made, it's about 4' of 2" x ¼" strip stock with 2 holes drilled along the edge such that I can bolt it to the yoke with 2 of the U-joint bolts, but still get a socket over the nut.

Once you get the pinion in, you put on the solid spacer, then some shims, then the bearing, then the yoke, then the thick washer, then the nut.

You can't really get it right with the carrier in there. The friction from it makes it impossible to tell when you get the pinion preload right. So you have to take it out. Of course, all of this won't change the pinion's location in the housing, so your backlash setting shouldn't change.

.010" of backlash is OK, but a little on the high side for new gears. I'd shoot for something more like .007" - .008".

 

OKie I got it. I need a dial indicator to really check backlash. I'm guestimating based on feel.

Guess I also have to learn how to use one.

I'm gonna order the solid spacer today. Guess I wont see it til monday.

Thanks alot for the response. Very appreciated!

-- Joe

 

Wait a minute! When you first mentioned your backlash, you said you held the ring gear and spun the pinion yoke to determine the backlash. That is the wrong way to determine backlash. You hold the pinion yoke and move the ring gear up and down. That is where backlash is measured, and believe me, it makes a big difference. If you have .010" backlash when measured by holding the ring gear, then you really have like .025" backlash when measured properly. This could be your vibaration.

 

I noticed that tonight, gonna re-shim the carrier once i get the pinion squared away.

RB83L69,

Two problems. Got the spacer + shim kit today.

When I remmoved the pinion out of the car, I beat it to death with a 10lbs hammer to get it out. This bent the top on one of the sides ever so slightly, and somewhar ruined the first two threads.

Suggestion?

Worse so, my partnet didn't "catch it" and it fell about 6 feet onto the concrete floor. (uggg). Doesn't look chipped, bent, or cracked.. Spent an hour looking at it..

Suggestion?

-- Joe

 

If you think you bent the top ever so slightly, this could add to your vibration problem. Think about it, a slighty bent pinion shank spinning at 3000 RPM is going to vibrate. So if your reshimming the carrier cures the old vibration and the pinion causes a new vibration, you're going to be pulling your hair out trying to figure it out. Keep in mind that a tall gear is going to vibrate, that is the nature of the beast. I just put in a 3.73 and at highway speeds there is a noticable vibration, and all my polyurathane bushings really transmits that vibration quite a bit.

 

If you can see that it's bent, it's wacked. It's probably also mushroomed. If that had happened to it during the install process, that could also explain the vibe problem.

Incidentally, that's exactly what I was trying to find a delicate way to say, when I told about honing the bore of the tail bearing.

You may need a new gearset. At least, if it was me, I don't belive I'd try putting a known damaged gear back in, and expect it to run right, in my own car.

fisher is right about the backlash measurement method, I didn't catch your wording earlier; you hold the pinion still, and measure the movement of the outside edge of a ring gear tooth. It's best to measure it at 3 or 4 places around the ring (measure it, turn the ring ¼ turn, measure again, etc., since ring gears are rarely perfectly flat), and shoot for an average of .006"-.008", with no point on the ring below .005". If you're setting up used gears, you can go to .010", since that much metal will wear off of them fairly quickly during break-in.

You can get a dial indicator and magnetic base fairly cheap (and won't cost you much either) from McMaster-Carr www.mcmaster.com http://www.mcmaster.com/catalog/109/html/2065.html

 

Well the gear itself looks just fine.. I was thinking of grinding off the first 2 threads off the shank, and then going over the rest with a die to make sure they're straight.

This is un-related to the vibration from the other day, since I did this last night..

What _was_ the vibration was the fact that the nut wasn't tight at all. There was no preload, there was play, and the crush sleeve wasn't harmed.

What i'll prolly do today is re-assemble with the crush sleeve until I get preload, and road test it. If no vibration, I'll take it out and use the solid spacer.

Guess I'll use a slide hammer next time, instead of a sludge hammer. doh..

-- Joe

 

Hone the tail bearing.

Good luck!!

 

Got it back together. preload seems right.. setting backlash was.. interesting.. I always set backlash in one spot before.. This time I set it, and spun the ring around.. it was tigher in a different spot.. So I re-shimmed it and set backlash at the tightest spot..

When I set backlash instead at hte looses spot, the tight spot would almost bind a little.. I figured this would blow up if I left it like that.

I might drop this thing off at a rear end shop this week and have 'em double check my work.. The 9" fords i've done were easy, this 10 bolt is a nightmare..

-- Joe

 

Update.

I drove the car like twice over the summer. Spent most of the fall/winter on motor mods, bigger blower, ecm updates, new exhaust, etc.

On the lift, at 60+ mph the car vibrates like hell.

So I pulled both axles.

Same thing.

So I pulled the carrier.

Same thing..

So I figured since when I did the rear, I didn't change the races, this time i'll do ALL the bearings again. (on the pinion)..

I pulled the pinion nut off.. omg. the nut was total junk.. the threads on the pinion are a little messed up. gonna fix that tomorrow.

I'm gonna brake hone the old bearing out and put the pinion back in (after the threads are fixed) and check preload and recheck pinion depth.

I have a dial caliper.. It can do depth.. If I set it to the dept (2.311") how do I find the center of the axle??


Gear pattern..

My gear pattern looks. well I dunno.. The wear mark on the pinion
goes fairly deep, and is about 3/8" away from the edge (small edge).

The ring gear is deep too. I dunno how to explain.. If I snap some pictures, can someone give me their opinion??

-- Joe