Reworking an 8 1/4 and can't find ?

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memike

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Is there a thread anywhere here that has allot of information on these 73 up A body rearends ?
I would like to rebuild and set up the gears myself, but looking for info here I can't find much.

I need all the nuts and bolts to the hubs (I need to put that in the wanted thread) :glasses7:
Has anyone here ever built a 8 1/4 :glasses7:
I will be looking and bringing info here to this thread as I look today and drink :coffee2:

Thank you for any involvement bringing (hopefully) all information to this thread :happy1:
 

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I'm also gearing up for an 8 1/4 build and need all the tech help I can get..

Hopefully someone will chime in with tech info and part sources!
 
I upgraded my '75 8.25 from 2.45 open to 3.55 SG.
I got ALOT of help from 69Mope. :prayer:
What a wealth of information.
I procured one from a '92 Dakota 2wd.
Went in like a champ and works like a dream.
Maybe ping him up.
Also, got good info from DR. Diff. :prayer:
 
One of the hardest tools to find when working on these is the tool you use down the axle tube to adjust the carrier bearing adjusters. I wound up making one. I found a bolt that the head was just a little to big. I wound up grinding the flat sides of the bolt til it would fit into the adjuster. I ground the flats at an angle so the bolt head wouldn't slide all the way thru the adjuster. I then welded a 1/2" drive 7/8" socket to the threaded part of the bolt. Now I can use a long 1/2" drive extension thru the housing ends to adjust the carrier backlash and set the carrier bearing pre load.
 
One of the hardest tools to find when working on these is the tool you use down the axle tube to adjust the carrier bearing adjusters. I wound up making one. I found a bolt that the head was just a little to big. I wound up grinding the flat sides of the bolt til it would fit into the adjuster. I ground the flats at an angle so the bolt head wouldn't slide all the way thru the adjuster. I then welded a 1/2" drive 7/8" socket to the threaded part of the bolt. Now I can use a long 1/2" drive extension thru the housing ends to adjust the carrier backlash and set the carrier bearing pre load.

I here that SGBARRACUDA I found out a 2 1/2 pip fitting fit's and I screwed a 1/2 pipe into it and slide it in and turn my pre-load :glasses7: I seen it on a u-tube video on building a 8 1/4 yesterday, but it was a truck 8 1/4 :coffee2:
 
I upgraded my '75 8.25 from 2.45 open to 3.55 SG.
I got ALOT of help from 69Mope. :prayer:
What a wealth of information.
I procured one from a '92 Dakota 2wd.
Went in like a champ and works like a dream.
Maybe ping him up.
Also, got good info from DR. Diff. :prayer:

Thank you for the info swies :glasses7: I believe the rear end I have is out of a 73 Duster 318 car, I will be keeping it to slide in Victoria :color:
But will never rule out anything, was it a disk brake rearend ?
 
Nope. It was a drum rear.
I did the bolt - socket trick to adjust my side load. Only thing to be careful of...USE AN EXTENSION WITH THE LOCKING MECHANISM ON THE END.
Suck to lose the socket in the tube..
Ask me how I know...
The rear housings were nearly identical. Just had to use bearing to fit the Dakota since the OD is the same but the ID is different.
I read lots of things / posts / blogs about having to grind some here or there etc. None of that happened. Went in smooth.
Adjust load, Set pinion depth.. (Special thanks to 69 Mope there. No measuring required, just read the numbers and do some math) Then Torque the pinion.
Done and Done.
 
Nope. It was a drum rear.
I did the bolt - socket trick to adjust my side load. Only thing to be careful of...USE AN EXTENSION WITH THE LOCKING MECHANISM ON THE END.
Suck to lose the socket in the tube..
Ask me how I know...
The rear housings were nearly identical. Just had to use bearing to fit the Dakota since the OD is the same but the ID is different.
I read lots of things / posts / blogs about having to grind some here or there etc. None of that happened. Went in smooth.
Adjust load, Set pinion depth.. (Special thanks to 69 Mope there. No measuring required, just read the numbers and do some math) Then Torque the pinion.
Done and Done.

I want to thank you for your input on this swies :color: I will be looking in on 69 Mope and his post's on this :glasses7:

From what I am seeing this 8 1/4 rear end is built and uses the same system as the 10'' Chebby rear end. Still learning and my friend said he can rebuild it but said I could do it at his shop with his super vision and tools :glasses7: I feel like this is a straight forward axle bearing and pinion bearing replacement and get some dial reading on the end play and pinion depth, looks like there has been no tech info anywhere, but I am still searching :glasses7:
 
I have a little info in my 8.25 built to race thread. I upgraded my axle shafts to the larger 29 spline from 27 spline. And got a new track lok with 4:56 gears. Mine came with 11" drums added by someone off a larger car. All my parts where from doctor diff. Nice guy and best prices I could find.
 
I have a little info in my 8.25 built to race thread. I upgraded my axle shafts to the larger 29 spline from 27 spline. And got a new track lok with 4:56 gears. Mine came with 11" drums added by someone off a larger car. All my parts where from doctor diff. Nice guy and best prices I could find.

I have been looking at his site, rear end work can be pricy I see ProStocker :glasses7:

I put a tape on my backing plates and they are 11'' across out side to out side :glasses7: what size !!! Shoot #-o shoes and Drums do I need to buy #-o Are my backing plates 10 then ? ? so many things to learn :pale:
 
One of the hardest tools to find when working on these is the tool you use down the axle tube to adjust the carrier bearing adjusters. I wound up making one. I found a bolt that the head was just a little to big. I wound up grinding the flat sides of the bolt til it would fit into the adjuster. I ground the flats at an angle so the bolt head wouldn't slide all the way thru the adjuster. I then welded a 1/2" drive 7/8" socket to the threaded part of the bolt. Now I can use a long 1/2" drive extension thru the housing ends to adjust the carrier backlash and set the carrier bearing pre load.

I made two adjusters so I can slide one in each tube and it makes setting them up a lot faster than switching from side to side. Since we do a lot of 8.25" work

we have T-handles welded onto the bars and don't need a rachet to adjust them.

It's a must to build an adjustment wrench before you ever get started working on these rearends.

Tom
 
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