Hey guys, I have an opportunity to purchase an 8.75 locally and i had some quick questions making sure it is indeed an A body rear as its listed. The seller says it came out of a 70 duster, it has 3:23 gears, a 489 casing with limited slip. In his ad he called it posi so i was thinking maybe he wasn't as knowledgeable in knowing if it would fit my 73 duster. No picture was added but i want to go look at it. What am i going to need to look for or measure to make sure it is indeed an A body rear? I want to keep the swap as simple as possible, that why i didn't go yank one out of a truck. Thanks
Questions about an Abody 8 3/4
- Thread starter 7DUSTER3
- Start date
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Small bolt pattern, 57 1/8" wheel mount to wheel mount, 52 5/8" backing plate flange to flange, 43" perch centers.
green1
Well-Known Member
Jack one wheel up, if you can spin it, no posi.
Everybody seems to call them "posi", even some dyed in the wool Mopar people. Take the measurements that crackedback has for you, and then spin either axle and make sure the other axle is spinning the SAME way. If it's not spinning the same way or not spinning at all, it is an open center, if it spins the same way, it's a suregrip. Being it's a 489 case and from a 70 car, it's most likely gonna be an Auburn "cone" style suregrip. How much is the asking price??? Geof
His email is 70novaguy****** so i figured he wouldn't know much about them. I was going to test for the sure grip to dbl check. Are there any numbers or castings i need to check for on the pumpkin or is it all based on measurement? I'm not to fond of the the small bolt pattern. How much roughly will it cost to drill the big bolt pattern? He is asking 800 for it firm. I haven't really priced them out as much as i should i guess but i figured that would be within reason if i were to buy one from a junk yard and have it shortened. Am i wrong in this assumption? Thanks for all your responses.
For $800 I'd want to pull the pumpkin to see what it really has in it.
No numbers on it will tell you it's an A rear. Got to measure.
It will cost you about $75-175 to have the SBP axles and drums drilled, IIRC
Check out Sutton Engineering. They do that stuff
http://www.suttonrears.com/machine.htm
You might be better off looking for a housing, get it shortened, and buy BBP axles and do it that way. It will cost a bit more, but you'll get exactly what you want and can reuse the BBP drums you currently have.
No numbers on it will tell you it's an A rear. Got to measure.
It will cost you about $75-175 to have the SBP axles and drums drilled, IIRC
Check out Sutton Engineering. They do that stuff
http://www.suttonrears.com/machine.htm
You might be better off looking for a housing, get it shortened, and buy BBP axles and do it that way. It will cost a bit more, but you'll get exactly what you want and can reuse the BBP drums you currently have.
I sold a complete 8 3/4 A body rear end with a 3.23 cone type sg for $500 two weeks ago.
Quick question for you intelligent minds out there, I came across a 8-3/4 rear out of a 67 monaco. If i am correct in my research, the track is 59.2" and the perches are 44" across. Will these dimensions give me enough play to run it as is? Or will i still need to shorten the axles?
MR.7DUSTER3
His money, My time
Bump,
Any Body
Any Body
'64 Cuda
Well-Known Member
I've heard of people doing it with the correct positive offset wheels to fit them in the wheel wells. I've also heard of people just forcing the springs apart to fit the existing spring perches onto the springs. Wouldn't recommend that though.
caferacerx
BAND MEMBER
the monaco is a C-body so it will be WAY to wide to fit in an A-body
A 67 monaco has a mount to mount of 61.75". Perches are 46"
It's about 4.5" wider than an A body rear and would require some serious offset wheels. A 68-70 B rear is 60 1/8" so it's almost 2" longer than than a B Rear.
It's about 4.5" wider than an A body rear and would require some serious offset wheels. A 68-70 B rear is 60 1/8" so it's almost 2" longer than than a B Rear.
MR.7DUSTER3
His money, My time
But if the price is right .it still could be cut down to fit our Duster right ??
Bob / Bryce
Bob / Bryce
If it's cheap enough, buy it and have it shortened. Those axles may be able to be resplined.
Did you guys ever find Sutton's phone number?
Try 562-266-1666
caferacerx
BAND MEMBER
welcome to the exciting and often confusing world of mopars 8 3/4 rear end
MR.7DUSTER3
His money, My time
One more question ,would it be wise to make the rear end a little wider than a stock a body rear end to get a little more clearance on the springs ?
Bob
Bob
No, I'd get the wheels and tires you plan to run and cut it down to the length required.
If you don't have the springs relocated, it's tough to cut an A rear much shorter than std length. The U bolts start to get on top of the housing ends.
If you don't have the springs relocated, it's tough to cut an A rear much shorter than std length. The U bolts start to get on top of the housing ends.
MR.7DUSTER3
His money, My time
That's why I thought if we went a little bit bigger than stock length ,we could get the off set we wanted and not have problems with tire clearance on the spring side . Does that sound logical ? or am I looking at it wrong ,We are very open for your suggestions.You guys that have done this swap tell me your combo ie. wheels,offset, tire size and post pics if you have them I would like to see different ways of doing this.
Thanks guys for all of your responses.
Bob
Thanks guys for all of your responses.
Bob
caferacerx
BAND MEMBER
you are looking at it correctly decide what wheels you want to use and modify the rear to fit, just make sure your measurements are precise.
Crackedback that number for Sutton worked. I called and got a quote of 1375 for everything including 3:55s and a suregrip with green bearings. I pick up the rear end on Monday and it should be in Whittier by the end of the week. Now to finally decide on what wheels i want... THANKS AGAIN
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