how to guide for 7 1/4 to 8 3/4

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CrazyPete

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is there a reference out there for doing this swap? i know it seems pretty simple i just wanna know what im in for
 
is there a reference out there for doing this swap? i know it seems pretty simple i just wanna know what im in for


Fire away with the questions, it has been done a bunch around here.

First of all what car? Is it an A body rear that your swapping in?
 
ok heres my project my swapping car is a 76 dart sport was a /6 car now has a 383 a/t it has the crappy 7 1/4 i have a project/donor car im getting the 8 3/4 from which is a 63 dart that was a makeshift project car back in the 80's the guy got parts he claims were from a 69 dart gts which included a 360/340 4 speed and a 8 3/4 rear end well ive already sold the 4 speed set up now i wanna swap in the rearend. Its a 741 weak pumpkin but what i need to know will the springs bolt up to my 76? I have several 489 housings ready to bolt in the rear also is sbp so i figured id order axles from dr diff sometime i wanna know if theres a simple pic filled guideline to removing the springs from the car to make my swap nice and easy any tips welcome
 
Unbolting the rear spring hangers then the forward spring hangers, rolling the whole thing out from under the car at once sounds easy enough but... You'll need some very tall stands if you dont have a lift.
For some spending another 35 bucks for new U bolts is the best plan.
 
Start soaking the bolt a week or two before you are going to swap them out.
Take the tension off of the emergency brake cables, and un hook each emergency brake cable.
Un hook the rubber brake line where it comes down to the rear axle.
Remove the four bolts from the drive shaft.
There are four nuts on the front of both spring hangers, and two on each rear hanger, remove them for each spring. Pay close attention on which way the front hangers are oriented, if you switch them from side to side it will lower the car 1".
The rear end is now ready to take out of the car.

Your brake drums, brakes and backing plates will bolt right on the 8.75 axle, this will give you big bolt pattern brakes, and most likely 2.5 x 10" brakes. This requires the use of Dr. Diff axles.

Download the factory service manual which will show everything. The manual is a sticky somewhere on this site.
It is really pretty easy if you know the basics, and have a shop manual.
 
You may want to purchase the following parts depending on condition of these on donor car, and how far you wanna go. Here's a list of what I replaced and parts I purchased:
rubber brake hose, axle vent screw, rear axle brake lines, 20 axle/carrier nuts, a set of BBP axles from dr diff, inner axle seals, pinion seal, yoke straps, U-bolts, shock plates, shock washers, gear lube, 2 new U-joints,
I also bought new drums, brake hardware kit with adjuster kit, and new brake shoes.
Do you plan on cleaning up the housing and carrier, backing plates?
You may have to get the driveshaft resized.
I ended up getting more parts and farther into it then I initially thought I would. But I tend to be a little obsessive/compulsive....lol
The work itself is pretty easy, you shouldn't have a problem.
 
sweet thanks guys never done it is all ive replaced tons of gears axle brakes but never the whole assembly it seemed pretty simple just wanted some tips ill snap pics and do a write upas far as the brakes i got a big drum set up off a 69 newport that should stop the car very good
 
sweet thanks guys never done it is all ive replaced tons of gears axle brakes but never the whole assembly it seemed pretty simple just wanted some tips ill snap pics and do a write upas far as the brakes i got a big drum set up off a 69 newport that should stop the car very good

If they are 11" make sure the drums are in good shape.
11" drums are worth their weight in gold.
Re-man ones are over 100 bucks each.
10" you can buy two and still take your lady out to a good dinner.
 
You will need to replace the stock shock plates with 8 3/4 ones, U-bolts, and shorten the driveshaft approx. 2".
 
got the old 8 3/4 out today pretty simple thank god the bolts that were on there were ingood shape...except one whoch was rounded off so it fought my cut off wheel for about 45 min.............next up is removing the the 7 1/4
 
Ok im at the rear shackles do i just cut one of the studs or try to unbolt it from the frame? Im just worried about breaking the bolts
 
Unbolt the two nuts, the shackle is just a "C" with a plate on the side.
Slide the shackle out.

Reference mancini's racing website for an illustration of the shackle.
 
simple thanks man so far everything has unbolted pretty easy the E brake cables unhooked easy too even the brake line came right off btw the car is completely original still had stock shocks which were bad its nice having an old car that comes apart easy FINALLY!
 
well got it out today pretty easy o gotta say the oly issue i had was the shackles there studs not through bolts so i thought it would be a good idea to remove the shackle plate..Wrong needless to say i broke a bolt not a huge deal i guess just gotta drill it out and put a new bolt in.

pics thanks again for everyones help and advise
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