Axles

[VDOG]

Know this is an old subject, but im having my 69 12 bolt rearend worked on. The problem is both axles from Summit seem to be the same size, no right or left thus my drum overhangs on the right(passenger side) backing plate. Thought it was because I changed carriers. Has anyone else had this problem while doing a 5 lug conversion?

[Jim_PA]

All I can tell you is that the axles are supposed to be the same length.

[Green Machine]

Axles should be same length, only thing it could be then is mis-matched brake drums. Are the drums exactly the same ?

[VDOG]

Originally Posted by Jim_PA

All I can tell you is that the axles are supposed to be the same length.

See I was told that one side was supposed to be longer then the other. Also my left (driverside) axle has at least 2 inches of space between the axle backing plate and the rear wheel cylinder while the right axle backing plate sits on the wheel cylinder.

[VDOG]

Originally Posted by Green Machine

Axles should be same length, only thing it could be then is mis-matched brake drums. Are the drums exactly the same ?

I switched drums to and axles to see if there is any difference, still the same thats why I figured it had to be the rearend setup.

[EFI70Blazer]

Are your backing plates the same? I know for sure that 4x4 backing plates are different than 2wd backing plates. When i swapped a 2wd rear into my 4x4 i had to swap the backing plates along with the axles. My 4x4 ones had 2 1/2" brakes and the 2wd one had 2" brakes, thus making the difference. You may check your brake drums also. Make sure they are the same. Other than that, your axles should be the same size along with the tube length of your housing.

[VDOG]

Originally Posted by EFI70Blazer

Are your backing plates the same? I know for sure that 4x4 backing plates are different than 2wd backing plates. Other than that, your axles should be the same size along with the tube length of your housing.

My rearend is the same one that came with the truck. Due to the bolt breaking that holds the pin in where the axles meet. I had to change carriers and ring gears due to me destroying my old carrier.

[mvfd70]

Measure your axle tubes and make sure they are the same length. Measure your old axles too. Just make sure everything is the same. That'll give you a reference as to where to start.

[SCOTI]

Double check & make sure the axles seated completely into the carrier for the c-clips. When I got my first axles from Moser, the splines were not cut @ the same degree as the factory axles & they would not slide all the way in place.

I took several tries getting it right.

[VDOG]

Originally Posted by SCOTI

Double check & make sure the axles seated completely into the carrier for the c-clips.

My axles slide all the way in and are seated right on the center pin.

[SCOTI]

Originally Posted by VDOG

My axles slide all the way in and are seated right on the center pin.

Ok. I know mine were an issue & wanted to be sure.

Like mentioned, the axles (L & R) should be the same length. How do they compare vs. your original axles? Same length?

[VDOG]

Originally Posted by SCOTI

Like mentioned, the axles (L & R) should be the same length. How do they compare vs. your original axles? Same length?

Yes both axles match my old ones. Im still betting its the carrier. I know all carriers are not alike due to casting. This one came out of a 6cyl 67-70 truck because of the gears (either 3:55 or 3:73's). The 6cyl carrier and my old one have the same numbers on them. My axle tube on the right side appears to be shorter then the left. But if it is, then how could I have the same size axles?

[Jim_PA]

A different 12 bolt truck carrier would not require you to alter axle length.

It looks like there's something wrong with your backing plates. The convex part of the backing plate on the drivers side wheel looks like where the e-brake cable should go into the rear brakes. Why is that on the back of the truck?

From the pictures, something doesn't look right in that area, but I'm not 100% sure.

[EFI70Blazer]

Did you change anything besides the axle's, like backing plates or drums? Personally i would make sure those match if you did change them. You could have a backing plate for 2 1/2 inch brakes on one side and one for 2 inch brakes on the other side. Just looking at your pics it looks like one of them is more dished than the other.

[VDOG]

Originally Posted by Jim_PA

A different 12 bolt truck carrier would not require you to alter axle length.
It looks like there's something wrong with your backing plates.

Got a call from the rearend shop. The carrier from the 6 cyl althought it looks the same as my old one, I was told I need to get the numbers to get a matching ring and pinion instead of switching rings. The new carrier from the
6cyl is hitting the pinion and there is no play in the rearend. So from what im hearing it is the carrier.

[Jim_PA]

Originally Posted by VDOG

Got a call from the rearend shop. The carrier from the 6 cyl althought it looks the same as my old one, I was told I need to get the numbers to get a matching ring and pinion instead of switching rings. The new carrier from the
6cyl is hitting the pinion and there is no play in the rearend. So from what im hearing it is the carrier.

The carrier series has nothing to do with axle length, but I hope it works for you.

[EFI70Blazer]

Originally Posted by VDOG

Got a call from the rearend shop. The carrier from the 6 cyl althought it looks the same as my old one, I was told I need to get the numbers to get a matching ring and pinion instead of switching rings. The new carrier from the
6cyl is hitting the pinion and there is no play in the rearend. So from what im hearing it is the carrier.

For one, ring and pinion sets should never be miss matched, since they are run in together. The only way that your carrier could be wrong is if it was the wrong series. A four series carrier has the ring gear 1/4" closer to the pinion than a three series carrier. But in order to even install the carrier all the shims would have to be removed from one and put on the other. Even then things would either bind up or almost completely miss the other gear. Find out what carrier you have and the gear ratio you have. Also here is a thread that explains what measurements you should be getting and where to find gear ratio markings.


http://67-72chevytrucks.com/vboard/s...d.php?t=245747

[VDOG]

Originally Posted by EFI70Blazer

But in order to even install the carrier all the shims would have to be removed from one and put on the other. Even then things would either bind up or almost completely miss the other gear.
http://67-72chevytrucks.com/vboard/s...d.php?t=245747

When I pulled this carrier from the wrecking yard over 5 years ago, I did not know I needed the shims, pinion, or that I should have taken the whole rearend wheels and all. Just disconnect it from the driveshaft. We learn by our mistakes. The guy who helped me knew about as much as I did.
Now its going to cost me for not knowing, but it will be done right this time.
Thanks for the help guys.

[VDOG]

I found out my rear end repair is going to cost from $300 to $500 or find another one. Talked to a guy who says he has a 68 rearend with an original posi-traction still in it. He wants $350. I thought that was kinda of high. Going to look at it tomorrow. In the meantime, how should I clean up this surface rust? Por-15, DA Sander, then prime and paint? What do you guys think?

[mnunn454]

Regarding your most recent question, personally I'd sand/media blast it, then prime and paint it. If you do sandblast, make sure you cover/tape up everything. That sand and dust gets into absolutely everything.

Regarding a posi 12 bolt, I think $350 is in the ball park "IF":
It's the right gear ratio you need,
The posi clutches aren't all worn out
All bearings are in decent shape
Shows a good wear pattern indicating the setup is correct.
It's an exact bolt-in and you don't have to do any other mods to get it to fit
It solves the original problem of off-centered tires and drums

Otherwise, I'd think it's worth a lot less depending on its condition.

Good luck.

[VDOG]

Originally Posted by mnunn454

Regarding a posi 12 bolt, I think $350 is in the ball park "IF":
It's the right gear ratio you need,
The posi clutches aren't all worn out
All bearings are in decent shape.

I found another one for $150. This one was converted to leaf spring for a 56 truck. How hard would it be to turn it back to coil springs? Also its a posi with 3:55's in it.

[VDOG]

Originally Posted by VDOG

I found another one for $150. This one was converted to leaf spring for a 56 truck. How hard would it be to turn it back to coil springs? Also its a posi with 3:55's in it.

Ok this rearend is out of a 72 C-10. I was told that it would not fit under my 69. Also my new axles will not fit because they're too short. Help!!!!!!

[71tahoe]

Originally Posted by VDOG

I found another one for $150. This one was converted to leaf spring for a 56 truck. How hard would it be to turn it back to coil springs? Also its a posi with 3:55's in it.

Originally Posted by VDOG

Ok this rearend is out of a 72 C-10. I was told that it would not fit under my 69. Also my new axles will not fit because they're too short. Help!!!!!!

If it was originally from a coil truck it will fit. The panhard rod attachment point should still be there. ECE and maybe others make axle perches for converting to a coil spring rear that will weld on in place of the leaf perches. It would already have the 5 lug axles if it is an original 72 just about 1" wider. You will probably need a 72 rear brake hose.

If I'm missing the boat, someone correct me.

[VDOG]

Originally Posted by 71tahoe

If it was originally from a coil truck it will fit. It would already have the 5 lug axles if it is an original 72 just about 1" wider. You will probably need a 72 rear brake hose.

It was converted from coil to leaf spring to fit a 56 truck and it has 6 lugs. Is there anyway to tell what year it is just in case the guy has the wrong infomation?