Identifying rearend

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Dalton697

Dalton697

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I'm have a 1974 Dodge Dart Sport 360 I'm trying to identify the rearend, thinking about buying 3.91 gears for it but not sure what was the stock rearend for the car...I do know it does have posi:burnout:
 
Does it have a cover that is bolted on the back, or does the whole centre section come out the front?

Pics would make it a lot easier.
 
It is a front drop out and know its posi, but wasn't sure how you know difference between 741 and 742
 
some thing this last 3 #'s are what you are after
 

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Just looked at one site online that listed 72-76 dart as 8 1/4...is that some way I can verify my sport 360 is a 83/4
 
Stock rear on a 74' would be a 8 1/4".......
 

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Dalton697 said:
Just looked at one site online that listed 72-76 dart as 8 1/4...is that some way I can verify my sport 360 is a 83/4
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sure...look at the pics of the rear ends above...if your rear looks like the pic with the no cover and smooth rounded rear..its a 8.75....if not,,,then its something else...I have 3.91s w/sure grip in my 8.75 with a 489 case..love em
 
8.75 rearend is NOT stock for ANY A-Body 73+. Someone installed it at some point prior to you getting the car.
 
DUSTPAN340 said:
sure...look at the pics of the rear ends above...if your rear looks like the pic with the no cover and smooth rounded rear..its a 8.75....if not,,,then its something else...I have 3.91s w/sure grip in my 8.75 with a 489 case..love em
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I have that and a 3.23 sure grip in my 489 cases with solid sleeves, Nothing wrong with that! Though at some point, I'll get a set of 2.76 sure grip in a 489 and see with the top end with be with my 200R4 tranny :twisted:
 
Dalton697 said:
Thanks Rick that what it is, next question is a 8 3/4 pretty common swap for a body darts
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Yes! This is the rear that most people hunt for. That said they will also go for a 8.25 if the 8.75 is too much or a Dana 60 if an 8.75 isn't enough.
 
So your car is a 74, and the third member drops out the front. This rear end is definitely not original to your car. 8 3/4 differentials in A bodies (darts) ended in 72. It is entirely possible that your car has had an earlier 8 3/4 bolted in, a dead give away would be if it has the smaller bolt pattern (5 on 4") wheels on the back, as no A body 8 3/4 had the 5 on 4.5" bolt pattern, only if it has been modified with different axles and brake assemblies. Another possibility is that someone put a ford 9" rear end in the car - this would mean 5 on 4.5" bolt pattern wheels, a front drop out (like the 8 3/4) but the rear surface is not a smooth round surface like the 8 3/4", it has a raised portion for ring gear clearance.

And FYI, Chrysler products NEVER had possis, or posis, or lockers or whatever. They had sure grip rear ends. Just different manufacturers names for the same thing.

Hope this helps, good luck!
 
Dalton697 said:
Thanks Rick that what it is, next question is a 8 3/4 pretty common swap for a body darts
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With the stock rear you'll have the 4 1/2" bolt pattern. While the 8 3/4 is a common swap, the "A" body rears came with the 4"/ small bolt pattern wheels. Your easiest option is to build your stock rear with a good sure grip and the gear size of you choice. The next easiest option would probably be to go to a early "B" body 8 3/4 since it already has the 4 1/2 pattern. Unless you are going to make 400+ hp or use a 4 spd, i think a redo of your stock rear would be fine.
 
sorry for intruding just could use some info.
I thought all 8.75 5 on 4" rear ends were sure grips ?
do the number codes on the outside tell what gear ratio is inside? or do you have to open it up? I have one in my 65 cuda pretty sure it was a swap in but not sure.
And I have one in my 67 cuda that i pulled out of a 70 dart 20 years ago?
 
If you can do a burnout and leave two solid marks on the ground you have some form of a limited slip unit in the diff. The only sure way is to open it up and take a look.
 
No, not all 8 3/4 rears are sure grips, in fact in my experience most are not. You can tell the gear ratio easily by jacking the car up and counting how many revolutions of the driveshaft are required for one complete revolution of the rear wheels.
Oldmanrick is correct, it is also common to swap the slightly wider B body 8 3/4 into the A body, and all B body rears have the 5 on 4.5" bolt pattern
From the factory the paint daubs on the outside of the pumpkin told you what ratio, and if it was a sure grip, but they are probably long gone by now.
 
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