4.5" bolt pattern 7.25" rear axles

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OleNatesOlds

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Does anyone know all the models that have 4.5" bolt pattern 7.25" rear end axles that will fit the '69 a-body? Looking for the budget way to switch my 7.25 rear from 4" sbp to 4.5" bbp to match the fronts when I do disk brake swap. I went to the yard today thinking the '74 dart with /6 and 7.25" rear out there naturally had the bigger pattern, but it didn't. I started taking lug nuts off when something did not look right. So I measured them. "SOB!" Glad I didn't waste my time, energy, and money though (save for driving out there).

Is finding a '73-'76 a-body with front discs the only likelihood?...
It would be nice if an Aspen or 5th Ave axle would fit. There's a few of those out there. Thanks.
 
Why not get an 8.25? They are usually pretty cheap and easy to find. Much stronger than the 7.25. You will have to have your driveshaft shortened.
 
I already have the only good 8.25" in the area (and I've searched) that I'm saving for a '68 Barracuda. Shortening the driveshaft and purchasing another rear end starts veering off the 'budget' path I'm trying to stick with. Axle shafts at the yard are $18 a piece.
 
I am surprised there is one in there. Over a month ago there was a blue 74 4dr. If it's the same one. I have a bbp 7 1/4 in NC at my parents house in stony point. It's still under the car. If you are desperate we might could arrange something. It would be cheaper to re-drill though.
 
Yep - the same one is still there, but for how much longer? I had the notion for a few days that I might snag all four doors to replace those on my '69 Dart since they were pretty rust free and have side impact beams. It'll get crushed pretty soon I'm sure. Although, Chrysler's seem to hang around for awhile compared to GM and Fords since they are constantly rotating those out... There's also a '72 Valiant, '80 Aspen - usually something interesting/useful to me.

I'm asking around here to get axles re-drilled. It's tougher than I thought just to find someone capable.
 
OleNatesOlds said:
Does anyone know all the models that have 4.5" bolt pattern 7.25" rear end axles that will fit the '69 a-body?

Is finding a '73-'76 a-body with front discs the only likelihood?...
Click to expand...

Only A-bodies had axles that will fit an A-body housing without shortening. If you want big bolt pattern 7.25" axles, you'll need to get them out of a BBP A body with a 7.25

OleNatesOlds said:
It would be nice if an Aspen or 5th Ave axle would fit. There's a few of those out there. Thanks.
Click to expand...

The F body axles are longer. You can swap the entire housing over, they're only a little over an inch wider flange to flange, so you only need an extra 1/2" per side of clearance...

For that matter, grab an 8 1/4 out of an F body and use that.
 
I have 7.25 4.5 axles for sale. They are out of my 47k mi 75 Scamp that has disc brakes. I was going to sell them to another member, but it fell through because.... These require 5 bolts to mount, and a 5 bolt backing plate as well. The sbp axles are mounted with only 4 bolts on the flange.
 
roadrunnerh said:
These require 5 bolts to mount, and a 5 bolt backing plate as well. The sbp axles are mounted with only 4 bolts on the flange.
Click to expand...

Pattern is the same minus the extra stud. You can attach them just fine with 4, otherwise you'll have to add the studs on the axle housing.
 
Wait. I thought 7 1/4" was a c-clip axle. Why are there bolts holding in the bearing at the flange end? I thought that was a semi-floater thing? Then there would be access/balancing holes drilled in the flange as well. That wouldn't leave much meat to re-drill five new holes...
 
OleNatesOlds said:
Wait. I thought 7 1/4" was a c-clip axle. Why are there bolts holding in the bearing at the flange end? I thought that was a semi-floater thing? Then there would be access/balancing holes drilled in the flange as well. That wouldn't leave much meat to re-drill five new holes...
Click to expand...

Drill one additional hole and use the other four. The bolts seal the ends so grease don't run out.
 
Sorry. I'm referring to the wheel mounting flange. There would be three large holes in it. Or are you suggesting drill one extra hole in THAT?!
 
.............when u change to big bolt axles u need the matching brake backing plates[its a bolt on deal] and drums...u also need the side gears as well as their different...for the 7.25.....kim.......
 
Badsport said:
I wish you were closer, I have a complete 7 1/4 BBP collecting dust.
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i wouldnt mind having that myself lol
i read here somewhere that the axle tubes are bigger on a BBP 7 1/4 and that you have to change all the guts and seals
 
My dart came with big bolt wheels and they re-drilled the axles, brake drums and front hub and brake drums. It worked but I stepped up to an A body 8 3/4 and some new disc brakes up front.
 
I'm not gonna read all that BUT I have a useable 73 A body 7.25 with BBP axles drum to drum (which are 10x2.5")

make an offer!
 
I finally found some old timer at the local tech college who says he can re-drill and it will be cheaper in the end than sending it to Moser (shipping both ways). But my wheel mounting flange is definitely like the flange on these:

http://www.forabodiesonly.com/mopar/showthread.php?t=190427

So how do you re-drill something like that? Is there some geometry magic? Enlarge/offset center the stud holes all around or is that enough meat to rotate a few degrees and drill five new holes?
 
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