8.5 in rearend

spidereyes455

G-Body Guru
Mar 6, 2013
767
1,579
93
Northeastern PA
If you're looking for a completely new 8.5 new housing and all you will need to build a time machine and travel back to the 1980's. Cause as far as I'm aware no such thing exists. Which is why those rears bring a minimum of $1,500 dollars these days for a used one.
 
  • Like
Reactions: 7 users

86LK

Royal Smart Person
Jul 23, 2018
1,881
1,910
113
If you're looking for a completely new 8.5 new housing and all you will need to build a time machine and travel back to the 1980's. Cause as far as I'm aware no such thing exists. Which is why those rears bring a minimum of $1,500 dollars these days for a used abused ragged-out one.
fixed it for you
 
  • Like
  • Agree
Reactions: 6 users

Rt Jam

G-Body Guru
Mar 30, 2020
569
549
93
Ontario Canada
Supply vs demand has set the price on an 8.5"

You will be in competition with G body owners who are looking for a bolt in solution or someone building a Grand National.

What are you building?
 

doood

Amateur Mechanic
Sep 24, 2020
489
646
93
Supply vs demand has set the price on an 8.5"

You will be in competition with G body owners who are looking for a bolt in solution or someone building a Grand National.

What are you building?
I want one too. I'll pay more than OP.

Looking forward to learning a few things as I rebuild the abused ragged-out rear.
 
  • Like
Reactions: 1 user

doood

Amateur Mechanic
Sep 24, 2020
489
646
93
If you're looking for a completely new 8.5 new housing and all you will need to build a time machine and travel back to the 1980's. Cause as far as I'm aware no such thing exists. Which is why those rears bring a minimum of $1,500 dollars these days for a used one.
This is too bad. I've learned it is the position/angle/orientation of the 'ears' on the g-body 8.5" pumpkin/housing that was unique.
 
  • Like
Reactions: 1 user

PBGBodyFan

G-Body Guru
Mar 3, 2009
792
1,218
93
Wisconsin
This is too bad. I've learned it is the position/angle/orientation of the 'ears' on the g-body 8.5" pumpkin/housing that was unique.

I never heard of this, it would be the same as the 7.5" in g-bodies.

It's nice there are more options out there now, people use Ford 8.8"s out of certain Mustangs, aftermarket Ford 9", Explorer 9" rears, etc. That said I'm still a g-body 8.5" guy myself, direct bolt in(ok, grab the driveshaft too), less power loss than a 9" and is enough to handle whatever I'm throwing at it. I put in a junkyard unit with almost 200k on it in 1999 (GN had 191k on the last Carfax before a theft/strip) and ran it with just a fluid change until 2017 before having it rebuilt and the stock posi unit was still in good shape, the builder offered to buy it from me but I still have it. The other 8.5" is from a 442 that I just freshened up, looked just fine inside, no idea the mileage. Many out there aren't ragged.
 

wskirvin

Master Mechanic
May 22, 2017
325
423
63
Indianapolis, In
Be careful when looking at getting one. i bought one that was pretty crusty for $1000 and still had to rebuild it.
 
  • Like
Reactions: 1 user

scoti

Royal Smart Person
Supporting Member
Sep 5, 2019
1,939
3,333
113
Texas
This is too bad. I've learned it is the position/angle/orientation of the 'ears' on the g-body 8.5" pumpkin/housing that was unique.
G-bodies had their own C4L set-up that required GM/G-body spec'd mounting points for the housing 'ears'. The arrangement was the same for any rear GM housing intended for a G-body.

GM A-body & B-body cars used a similar rear suspension layout but the actual housings were different vs a G-body. The mount positions for the upper links on the housing pumpkin were probably the same as GM wouldn't invest all that $$ into one design for one line of vehicles (excluding the vette). Since the housing widths were different (wider), the lower link positions would be different (farther apart).

Swapping to a similar set-up converging 4-link & similar width (like what's under a Fox body Mustang) is where there are differences in the housing mount locations/orientation.
 
  • Like
Reactions: 3 users

doood

Amateur Mechanic
Sep 24, 2020
489
646
93
I never heard of this, it would be the same as the 7.5" in g-bodies.

It's nice there are more options out there now, people use Ford 8.8"s out of certain Mustangs, aftermarket Ford 9", Explorer 9" rears, etc. That said I'm still a g-body 8.5" guy myself, direct bolt in(ok, grab the driveshaft too), less power loss than a 9" and is enough to handle whatever I'm throwing at it. I put in a junkyard unit with almost 200k on it in 1999 (GN had 191k on the last Carfax before a theft/strip) and ran it with just a fluid change until 2017 before having it rebuilt and the stock posi unit was still in good shape, the builder offered to buy it from me but I still have it. The other 8.5" is from a 442 that I just freshened up, looked just fine inside, no idea the mileage. Many out there aren't ragged.
To clarify: the other 8.5" rears out there do not have ears (leaf spring rear) or do not have ears in the right spot (A-Body). There are conversion kits with offset UCA and LCA brackets to correct the issue with the ears on the 8.8 Frod and 12-bolt, etc.

If you have an 8.5 that you want to sell and you are within 800 miles of Philadelphia, I'll drive out to you and take it off your hands for $1500 so long as it can at least be rebuilt. I have absolutely zero interest in putting a ford rear in my Monte Carlo; I'd like to use the original equipment for the platform. Currently I have a 26-spline 7.5 with quick performance clutch posi. If I ever build a 7.5 I will use truetrack and 28 spline with 7.625 ring gear. By all accounts, that should survive 350 WHP.
 
  • Like
Reactions: 3 users

GBodyForum is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com. Amazon, the Amazon logo, AmazonSupply, and the AmazonSupply logo are trademarks of Amazon.com, Inc. or its affiliates.

Please support GBodyForum Sponsors

Classic Truck Consoles Dixie Restoration Depot UMI Performance

Contact [email protected] for info on becoming a sponsor