7.5 rearend swap

[posssum47]

I just changed out my 7.5 differential 3.73 ratio with a salvage yard 7.5 and 3.73 ratio due to pinion bearing failure, after installing new drums and shoes I am getting a clunking sound from the drivers side wheel area, I had the brakes checked and no problems there but I am told that the salvage yard axle also has pinion problems. My question is would the pinion bearing make such a sound if it is failing? the original differential made a grinding sound when it failed. I didn't correctly phase in the driveshaft with the pinion flange because neither original flange or salvage flange had markings I am told that would only cause vibration and not a loud clunking sound. I am also told that I may have a different backing plate on the salvage unit, I had 10 inch drums and shoes on the old unit and the salvage unit had no drums when I pulled it so I just assumed it was a 10 incher also. The salvage unit seems fine, no noise other that the clunking sound when I apply the brakes, doesn't happen every time.

 

[Insanejughead]

I've never seen a 7.5" axle with 10" brakes, but, I'm not saying you don't have them.


I wonder if the axle you swapped has a limited slip differential in it... That could cause a sound similar to what you describe.

Also, try re-tightening your U-bolts. I kinda had the same noise every once in a while when I swapped axles (just last month), and I think that the axle tries to shift under the leaf springs, just minimally, but enough, as the vehicle moves forward and backward.


I'm no expert on rear axles, but I've done some work on them. I hope this helped.

 

[Mac]

I've never seen a 7.5" axle with 10" brakes, but, I'm not saying you don't have them.

Brake size is solely based on truck GVWR (4580 lbs), not axle or motor, at least on 2000 and newer.
Dave

 

[SenorNoob]

If I remember right early Ranger 7.5s at least were either/or usually 9 inch on the 2wds and 10 inch on the 4wds. It's a pretty common question at the parts place.