SF_Ripper
Well-Known Member
Can a 7.25 be upgraded with spindles to a large bolt pattern? Or, is the only solution to go with a 8.75?
7.75 REAR END - UPGRADE?
- Thread starter SF_Ripper
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Plymouth 65
I'll be in the shop
You could use a 8.25 in BBP. 65'
Professor Fate
Push the button, Max...
Spindles? We'll pretend you mean axles. No BBP replacement axles are available for the early 7.25 that I've ever heard of. Adapters are your only option to go BBP with the early ('72 and earlier) 7.25. Other differential options are the '73 and later 7.25 (no, the axles don't interchange between early and late diffs), the A body 8.25 (offered '73-'76), the 8.75 (which will still require aftermarket 4.5 bc axles and B/C/E body brake assemblies), or a narrowed Dana 60.
A non-Mopar option is the Ford 8.8" rear out of an Explorer. Do a search in the Drivetrain forum for more info on this setup.
A non-Mopar option is the Ford 8.8" rear out of an Explorer. Do a search in the Drivetrain forum for more info on this setup.
Agree on the 8.8 being the new budget go to!
Dr Diff will make you whatever axles you want, plus the later 7 1/4 was big bolt pattern.
SF_Ripper
Well-Known Member
Sorry, got a ton-o-**** on my mind. Axles. I'll be checking out the drive train forum ASAP. Thanks for the reply.
SF_Ripper
Well-Known Member
I bet they would $$$
Well, they ain't free.
Professor Fate
Push the button, Max...
Well, I'll be a monkey's uncle... Yer right, Rusty- Doctor Diff does offer conversion axles for the early 7.25. Must be a relatively new offering, I had never seen those on his site before! They might even make the early 7.25 somewhat durable to boot.
OP, here you go:
Mopar Axle Pkg 7 1/4" A-Body 5X4 1/2" Bolt Pattern (pair) (doctordiff.com)
And that's dirt cheap for a pair of axles, kiddo. I assume you still need to score some B/C/E brakes for them, though.
Edit: He also offers 5x4.5 BC 9" or 10" drums as part of the package- it may mean you don't need B/C/E body brakes (like you do with most 8.75 axle packages), and these axles use the standard A body flange offset? He's on vacation until Aug. 4, so you'll have to wait until then to call and ask!
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SF_Ripper
Well-Known Member
I'm SURE I had looked on the good Dr.'s website for a solution before but, didn't see this! Thanks so much for pointing this out to me - you've won the internet for the day! I certainly like this $298 dollar option better than buying a whole rear end. And I gotta say - this all started out with wanting the reliability of disc brakes up front on a newly acquired '69 notchback. It's been a bit like plumbing repair in an old house - find a small leak, and you've got to tear down walls to repair what lay above stream. At least now - the end is in sight. THANK YOU!
cudamark
Well-Known Member
Not all of them. Starting in '73, A-bodies have 3 rear axle options. a 7 1/4" with 9" brakes and SBP, a 7 1/4 with 10" brakes and BBP, and the 8 1/4" with 10" brakes. The axle shafts do not interchange with any of them. The 7 1/4 with 9" brakes use the same axle shaft and bearing as the '72 and older 7 1/4. The 7 1/4 with 10" brakes use a different axle bearing than the 9" brake version. Regardless of brake size, the 7 1/4 rear end's weak area is the side gears and spider (pinion) gears, not the axle shafts. With enough horsepower, any part will break though....even 8 3/4's will snap something with enough power. If someone made some super strong side and spider gears for one, they could handle some decent horsepower.
SF_Ripper
Well-Known Member
F
ound this on the web...
Where did I say "all"? Chrysler used the small bolt pattern clear through 1976 on base models with small drum brakes.
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