Swapping in a 9 1/4

[Woodys72]

Hello, I am looking into a rear end for my 72 Satellite. I have been out looking for a 8 3/4 sure grip for replacement and I came across a 9 1/4 with 3.55 gears and suregrip. Looking at the mopar rear end cheat sheet the sizes seem perfect if the 9 1/4 came from a B body. Anything I should look out for? Parts still available for the 9 1/4, any known issues for swaps? Thank you in advance.

 

[YY1]

Measure for sure.

Lots of 9 1/4s used in trucks up into the 2000's

WAY too wide.

3.55 was common gear ratio in truck axles as well.

 

[Don Frelier]

I had a 9 1/4 in my 77 Fury, it had a towing package.
I don't know if the width differs from early 70's to late 70's.
I agree measure it, the yoke may be further forward as well and a bigger size which could affect driveshaft length.
That's a big heavy gear for sure.

 

[wyrmrider]

I've seen them in C bodies but never in B
please confirm
which Satallite
Wagon, tow package etc
what MOTOR AND trans
thanks

 

[bm02tj]

late 73 on used 9 1/4 in B bodys
check the width as there is lots of different ones out there

 

[Daves69]

.......http://www.hamtramck-historical.com...ataBook/1974/74_Plymouth_engineering_0029.jpg

SG available for one if you need it...........

 

[wyrmrider]

I had a 9 1/4 in my 73 Satellite Station Wagon- Trailer Tow and 400
I've just not seen one in a 72 or earlier
Real Common in 73 C bodies

 

[Woodys72]

I asked him for the width from flange to flange and he told me 57.8” with a tram bar. The sizing seems right. I just don’t want to drive a few hours to figure out it’s not going to work. It’s a Satellite Sebring with the original rebuilt 318 for now, but there are future plans for a swap. I’m tired of the one wheel peel outs and wanted Suregrip but didn’t want to spend money on the 8 1/4 the car currently has.

 

[rumblefish360]

Besides the width and spring lead have Dimensions, the spring pearches have a different, bigger size hole for the locating pins on the spring. The 9-1/4 uses the ISO mounts. The rubber of the biscuits fit inside. I have used washers to help locate the system until the U bolts were tightened. They haven’t moved in 15 years.

Also *I think* you will need to shorten your driveshaft, I’m not sure on the snout length. But, *I Think* it is longer than the 8-3/4.

I pirated one from. ‘78 Cordoba, 400/727/P code car. It was a bolt in on my Magnum.

Most every part is available for the 9-1/4. Sure grips, yokes, seals, etc...
You’ll need to poke around for parts a little bit but thee out there.


Check Summit or places like US Gear, Yokon, Richmond for available gear ratios.

 

[Kernel Sanders]

I don't know where you are in Ontario but I have a complete 8.75 for sale on kijiji. Complete, almost everything new, ready to assemble and run.

Its a 73 but ISO delete, 3.55 gear in a 489 case with clutch type suregrip new clutches. New tapered wheel bearings, almost new 10" drums. Swaybar with all new bushings. (bearings, seals, gaskets, clutches and SG additive are from Dr. Diff). This was for a 74 charger which has been sold.

I am in Ottawa, sorry wont separate and I'd rather not ship due to size and weight.

https://www.kijiji.ca/v-view-details.html?adId=1228473963

 

[Woodys72]

Does 55” from inside drum to inside drum sound about right? That’s what he’s telling me his is and that it should fit easily.

 

[m79ded]

My 79 Magnum with a tow package had it originally. Look at every 79 Chrysler 300 they had the same diff. Very strong but check the seat pads, it might be the rubber iso seat pads in the later cars, yours are the traditional type. You will need to weld seat pads if that's the case

 

[YY1]

There's an accurate axle chart sticky in the trans and axle forum.

 

[wyrmrider]

what trans and axle forum?

 

[YY1]

I thought it was in "engine and driveline", looks like it's in "brakes and suspension"

https://www.forbbodiesonly.com/moparforum/threads/8-3-4-axle-chart-the-good-one-sticky-please.60032/

 

[SureGrip]

I have a 9 1/4 in my 72 SSP with a 440/727.

I've not measured it, but the car was used for drag racing so I assume it was engineered out okay.

 

[wyrmrider]

great link YY1
THANKS