I've got an '85 Plymouth Gran Fury. It has a 7 1/4 rear end. Problem is we were going to put a 4.10 gear in it but the carrier is for the 2.23 or 2.26 gear that is in it, which we didn't know. In order to install the 4.10, we need a carrier that was a 2.76 or numerically higher, ie 3.21, 3.55. I'd also like to know about an 8 1/4. I've heard the later B-body 8 1/4 will fit without to much hassle. Just like to check to see if the B will work or if the F/M/J bodies will interchange. Thanks. In a pickle here.

 

NEVER NEVER NEVER use a 7 1/4 rear end. get a good 8 1/4 or a 8 3/4 a diifferant type but thought to be much better. i put 4.1 gear with a powr-lok in my 01 dakota. witha 3.9 V6. the 4.1 is fine for in town ONLY like i do. but on the hi-way you WILL lose MPG. be warned with a powr-lok or sure-grip. WILL try to spin the truck around if it brakes traction. NEVER punch it unless you KNOW you have good traction. you will be in the ditch looking the other way. even more the more power you have. i DO have some story's about it. IMHO.

 

On the '85 Plymouth Gran Fury that I have. Basically I need to know what 8 3/4 rear ends will fit. I've got an A-Body one, a B-Body one and one out of a '68 Pick up. I know the pickup probably won't bolt up but will either the A-body or B-body bolt up. I'm planning on using my rear springs off the '85. Thanks.

 

Lots of info with a longer search than I did.

http://www.dippy.org/forum2/index.php?topic=73.0

http://www.bigblockmopar.nl/tech/mop...le-dimensions/

http://www.440magnum-network.com/inf...rearaxle.shtml

Or a tape measure.