centering rear end

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midlife89

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I recently replaced all the bushings in my leaf springs and that helped with my rear end being off center,was 3/4",now is 1/2".which I have heard is not unheard of.But I recently bought new steelies,15x8 w/4 1/2 BS.The tires clear but the drivers side is awful tight.I have been thinking of moving the perches over 1/4" to give the drivers side a little xtra room to the outer wheel lip.Plenty of room to the springs.Will moving the perches hurt anything? Should I take the rear end apart or just weld them on with it together?
 
If I were going to move the perches, I would get a 1/2" offset hanger/shackle kit from Dr. Diff. You're doing all the work anyway, might as well get some extra clearance.

But, before I did that I would make sure that it was actually the perches that are off. Measure the distance from the quarters to the frame, and the quarters to the inner wheel tub and make sure it's the same side to side. No point moving the perches if the wheel tub isn't the same size.

Also, how do the leaf springs themselves look? What do the hangers and shackles look like? 1/2" isn't unheard of, but 3/4" is more than most of them are off. I would want to check that nothing was bent or damaged before I did too much fixing.
 
the springs are good,not sagging,and don't appear to be bent.Measured from the perches to the backing plates and they are the same.No sign of frame damage.Have thought of putting in the off set shackle kit but don't plan on going any wider and have 3" exhaust and off set shackle won't clear the exhaust,close now.I've replaced the shackles,previous owner pieced old ones together,used heater hose as shackle bushing.Thought I'd just split the difference by moving the perches,have plenty of room to the leaf springs3/4" and it's the sameon both sides the tire I'm using don' bulge on 8"rims,had them on my mustang.MT sportsman radials 26x10r15s
 
Another possibility is something I ran into on my Cuda. The rearend housing itself is centered yet the drivers side wheel stuck out about 1/2-5/8" farther than the pass side wheel. Found out the thrust pins in the sure grip unit were worn down so much I had to crank the bearing adjuster on the pass side in a bunch to get the proper backlash. After replacing the thrust pins with a new set it's still off a little but nothing like it was. Maybe 1/4" at the very most.

The only problem with cutting off and re-welding the perches back on is the rearend should be chucked up in a narrowing jig to hold the housing straight while you weld on it. Welding creates tremendous heat and will warp a housing real easy. The only way you could do it without jigging it up is to go super super slow. Weld a 1/2" let it cool a good while, weld a 1/2" let it cool a good while. You see where I'm going.
 
Thats what I was thinking. I figured moving the perches would be the easiest fix/cheapest fix.Ordering custom back spaced wheels isn't cheap.So should I be worried about the gear lube catching on fire.We're going to use a mig,don't think it would be as hot as a stick welder.If so I would pull it apart and drain it.
 
My bro in law told me the same thing.He used to build submarines.Rear end had green bearings in it when I got it
 
That seems like an aweful lot of work to get 1/4 inch. I got a different idea. Im assuming the bearing end play adjuster is still on the passenger side. Try swapping the adjuster over to the other side.
 
No end play adjustment with green bearings.1/4 could make the difference between the tire rubbing.They didn't rub on 15x7 wheels w 4"BS and side walls bulging.
 
Well, with no adjuster, how about pulling the axle out and pressing the bearing/collar on a little farther towards the flange. Will it still fit? If not is there room on the spline pattern to trim a quarter there and then move the bearing? But I guess if the bearing is all the way out, then my ideas are no help at all.
On mine, a couple of minutes with the tinsnips and no more problems. I can understand though if youre not into that. For me, it was a no-contest as the car was originally a plain-jane /6 fb runner.I kinda picked it for that reason, so I didnt have to feel bad when cutting,trimming, bashing, crashing, etc.
 
I wouldn't weld it up while it is all assembled. That's right next to the gas tank...
C
 
Why don't you keep it simple.....just slot the holes in the perches for the locating pins, slide it over and tighten her down? Or oversize the holes and use an offset bushing?
 
Put a 1/4'' or 1/2'' spacer in and be done with it that will move the one wheel out to be the same as the other side and there's no cutting or welding and it won't affect anything , I've done it in the past worked for me.

Mike
 
Why don't you keep it simple.....just slot the holes in the perches for the locating pins, slide it over and tighten her down? Or oversize the holes and use an offset bushing?


That's what I did. You can easily get it to move 1/4" to 3/8" by using a die grinder to slot out the perch hole.
If you need more then you can use a 1/8" or 3/16" spacer between the rim and the axle. You can't put too much between the rim and the axle unless you have really long studs.
Treblig
 
If it has green bearings the axles should be perfectly centered if their identical axles. What I was talking about earlier only concerns stock type adjustable bearings. Something isn't right there. Have you pulled the axle that's sticking out too far and checked to make sure the bearing is pressed all the way on? If not I'd do so. Another thought is I wonder if someone left the thrust pin in the center section when they installed the green bearings? If they did that's possibly the reason for the problem. When you assemble a rear with green bearings on the axles you usually slap one axle in and tighten it down. The first axle will go all the way in because there's nothing to stop it. Then you install the second axle and if the thrust pin is still in the differential it stops that axle from going all the way in. If you don't find a problem and since it has green bearings you could try swapping axles from side to side and see if that makes any difference.
 
both axles are out a little from stock,you can tell the drums don't sit in as far.When I pulled it apart last year to have the pinion and carrier bearings replaced,I had him pull the thrust pin out,they had left it in.I also took axles to make sure the bearings were pressed all the way on he couldn't move them any more.I will pull them to make sure they are the same and try swapping them side to side.I thought of slotting the holes but figured the perches wouldn't clear the u bolts,have to look at that.It has stock axles, are there diff bearings for stock and aftermarket axles?If I can slot the perch holes I'll have my bro in law weld up the other side to keep it from moving back.Don't want to have it move back or over torque the u bolts.They did,had a hell of a time getting them off,even though they weren't rusty.
 
are there diff bearings for stock and aftermarket axles?

Yes and no. Stock bearings will only work on stock axles. Green bearings will work on both factory and aftermarket axles. I'm not sure why stock bearings won't work on aftermarket axles but everywhere I see aftermarket axles listed they say "works with green bearings only"
 
Yes and no. Stock bearings will only work on stock axles. Green bearings will work on both factory and aftermarket axles. I'm not sure why stock bearings won't work on aftermarket axles but everywhere I see aftermarket axles listed they say "works with green bearings only"

It depends on the aftermarket axle. Dr. Diff's aftermarket axles work great with the factory tapered bearings.

As far as why it doesn't work, it probably has to do with the depth of the bearing surface on the aftermarket axles. And possibly the length of the axle itself.

I know I bought a rear end that had been cut down and new aftermarket housing ends put on it. It would only work with green bearings though, because the new housing ends weren't deep enough to allow the factory bearings to press all the way in. If the bearing surface on the aftermarket axles is made to match, it won't allow the tapered bearings to press on far enough.
 
I had the tires mounted on the rims so they are now mine.I have a 1/2" between wheel lip and the tire,wheel lips already cut when I got it.Found a wheel spacer I had from my mustang redrilled it to 5x4.The drivers side is still a little tighter but not much.I can live with it,as long as it doesn't rub.Going to replace the wheel studs w/longer ones,stock ones pretty short.I guess I'll find out more once I get it on the road.
 
The Yukon aftermarket a body axles were (are) shorter than stock a body axles so they could not be used with factory style wheel bearings as they wouldn't contact the thrust block in the center. This shortness is also why they could not be used with early style sure grips that use two piece side gears, there is not enough engagement in the second piece of the side gear and they tear the spline off. Ask me how I know... My second set of Yukon's were the cut to fit variety and I made them the same length as factory and used factory style wheel bearings (I prefer them.over green bearings).
 
Now I have a question about wheel studs.I planned on changing them any way since the studs were flush with lug nut when tighten even with out spacer.Popped out one stud to measure knurl/length.I have .472 knurl/1 1/2" length.The closest I've found is a .480 knurl/2 7/8" length.Will I have to drill the axle flange or will I be able to press them in.Also do you think 2 7/8 will be too long to run dog dishes?These are stock axles.
 
Now I have a question about wheel studs.I planned on changing them any way since the studs were flush with lug nut when tighten even with out spacer.Popped out one stud to measure knurl/length.I have .472 knurl/1 1/2" length.The closest I've found is a .480 knurl/2 7/8" length.Will I have to drill the axle flange or will I be able to press them in.Also do you think 2 7/8 will be too long to run dog dishes?These are stock axles.


You can cut them down to any length you desire and I don't think you will have to drill the axle , you should be able to press them in .

I'm glad you decided to use a wheel spacer and not narrow one side

Mike
 
As Mike said you can cut them down if their too long. I'm not sure you'll be able to get them pressed through with that much difference though. .008" is a lot for an interference fit IMO. You can always try and if they won't go then drill the hole bigger
 
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