1965 Dodge Dart stock differential advice

[blind bat]

I went through this recently. If your 7.25 is bad, you are better off finding a good replacement for a couple hundred bucks or upgrading.

Finding parts for an early 7.25" is difficult. I had to have a local machinist make me up pinion preload shims because nobody sells them including Dr. Diff. There are some shims listed but those are the pinion depth shims. The only axle bearings available are chinese and in limited quantities. I think I bought the last "standard quality" one from rock auto. I bought NOS leather lip axle seals from ebay.

Everyone I called said, "We deal with 8.25" and 8.75" rears. No one has asked us to rebuild a 7.25" in decades."

 

[Commando66]

Hey, it's Mike with the silver 67 Belvedere in Conway. You could place a wanted ad for the special 10x1 3/4" backing plates and hardware. Maybe a wanted ad for axles too but I think Dr Diff has new ones. Get any 8 3/4 housing and have it narrowed. There are quite a few local guys that have parts squirreled away too.

 

[Killer6]

At least with the 8 3/4 you'll have a rear that your car could have been ordered with and you'll still have small bolt pattern. They are damned well indestructible in a case like yours, and adding a Sure Grip won't solve the inherent weaknesses in the 7 1/4.

Actually, there 2 designs of 7.25" SG's. One is just like the 4-pinion powerlock 8.75", the other(which I have) is not, in either case the inherent weakness is spitting the spiders. The SG greatly reduces the failure rate of the 7.25, the problem is finding, and worse..rebuilding one if needed.