Doing my first rear end swap.

[doogievlg]

After 4 years of running my 7.25 behind my 360 I finally got a 8 1/4 rear end out of a 72 Scamp. What problems should I expect to run into? I got a new driveshaft, and wheels so the only thing i need are new brakes correct? Will I need knew you bolts? Ill post pics soon and I am putting it under my 73 Swinger.

 

[fishy68]

I'm pretty sure you will need new U bolts and shock mounts. You can verify that by measuring the tube diameter of the 7-1/4 vs. the 8-1/4. Pretty sure the 7-1/4 is 2-1/2" tube and the 8-1/4 and 8-3/4 rears are 3" tubes. Some guys say they make the shock mounts work by grinding out the holes so a 3" U bolt will fit. Haven't looked into doing tht myself.

 

[gtmopar]

You should always replace the u bolts when swapping out rear ends. They have a tendency to stretch and get work hardened over the years. Axle tubes should be 3" on both. Make sure the spring perches are in the same locations on both.

 

[fishy68]

You should always replace the u bolts when swapping out rear ends. They have a tendency to stretch and get work hardened over the years. Axle tubes should be 3" on both. Make sure the spring perches are in the same locations on both.

So your saying 7-1/4" have 3" axle tubes? I wonder why the U bolts and shock mounts I had for a 7-1/4 wouldn't fit a 8-3/4"? I agree about changing old bolts.

 

[VDART]

if your in a pinch-- I've parted a car that used all thread for the "U" bolt--- no telling how long it was there -- it was curved over the tube & lined up with the plate & bolted in placed.
Lawrence

 

[sst3193]

The tubes on a 7.25 are a half inch smaller in diameter, than an 8.25 or an 8.75. I took my shock plates to work and slotted the holes on a Bridgeport and haven't touched them since.