Came out of a 73 Duster BBP 10 bolt cover but it is not oval like a 8 1/4”. It has 10x2 1/2” brakes and C clip axles.
What rear is this?
- Thread starter SGBARRACUDA
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No I’m sure it is a mopar rear. 5 on 4 1/2” axles. Brake springs and parts look Mopar. 43” on center leaf spring perches.
Now why would they make a different 7 1/4”?
They made at least three versions. The ones in our early cars, then the big bolt c clip like you have and the Dakota. All three are somewhat different. There may have been more.
Thanks yes because I have a 75 valiant with a BBP 9 bolt cover that is different than this abortion.
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That doesn't show all the different 7 1/4s.
And also the years and models used is inaccurate.
Did you notice the 2006 date on the left side. Yes, your chart is more complete. I have never seen that one.
Some of the later ones supposedly have some parts that will interchange with Dana 30 and Dana 35.
I was ready to call it an 8.25 but then I remembered seeing them in the 80-89 Chrysler Fifth Avenue cars. Those car axles were 7.25s. I have pulled the rear brakes from 2 in the last year.
That is what I thought seeing the rubber fill plug. Then looking at the shape of the rear cover I said that ain’t right.
Charrlie_S
Well-Known Member
The early BBP 7 1/4 (don't know years) did not use "C" clip axles (had the bolt on bearing retainer). Also the main axle tube is 2 1/2 inch, but the bearing end was enlarged for the bigger bearing. I think (but not sure) "M" bodies used both the 8 1/4, and 7 1/4 rears. I think these 7 1/4 might have used "C" clips.
Oh yes this 7 1/4” definitely uses C clips.
Now this brings me to the next question. I have another more traditional 9 bolt 2 1/2” tube 7 1/4” that is BBP out of a 1975 valiant. Will a SG out of a early model like a 65 or 66 7 1/4” fit the 75?
I think it may be worth trying, because the second Gen 7-1/4 (at least the few I’ve dealt with) had positive axle retention. It may be best to locate a scrap big bolt pattern unit to disassemble to check, though. I think there was an axle spline drive angle change when they changed to a C clip axle, but not sure on the second Gen unit.
Well I have a friend of mine that is running a 71 318 904 Duster with a early SBP SG EARLY model 7 1/4. He is wanting to wind up with a SG BBP rear. We live about an hour apart. I was hoping to find out. I have the 75 BBP 7 1/4” here at my house.
Charrlie_S
Well-Known Member
YES.
I am doing one now. SG unit from a 65 Valiant sbp, being installed into a bbp housing with 3.91 gears.
Biggest problem with doing 7 1/4 rears is finding parts. I haven't seen any new 7 1/4 SG clutches, for sale in a long time, and those were very pricey.
Charrlie_S
Well-Known Member
Roy, that rear you have, are the axle tubes a small diameter where they come out of the center casting, and then get bigger? I found a rear in my stash like that, but the spring perches are further apart then "A" bodies, and has a large spring center hole, like for the rubber isolated springs.
PS: I don't thing the ring gear carrier from a bolt in axle rear will work in a "C" clip rear. At the very least, I think the axle end gear would be different.
PS: I don't thing the ring gear carrier from a bolt in axle rear will work in a "C" clip rear. At the very least, I think the axle end gear would be different.
Yes it does neck down where it goes into the center. But spring pads are 43” like a A body. Has standard size center hole in the perch.
Charrlie_S
Well-Known Member
The one I have the perches are about 45 inches apart. I have other rears that I can't get to as they are stacked on each other and have other things on top.
If you friend is not locked into Mopar parts, he might want to consider a 8 inch Ford rear, from a early V-8 mustang/comet/ granada/etc. Almost a bolt in, and lots of parts available. I have one of those, and without redoing the brakes, only have $300 in it. Got a pumpkin with 4.10 mini spool (limited slip available) for $200, at Sumpter county swap and the complete rear housing from a junk yard for $100.
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