Too much $ for 8.5?

[64nailhead]

Finally found an 8.5" with 3.42s out of a gn. Very close to home and supposed to be stock but has had regular oil changes. Guy is asking $1200... thoughts?

If it's a factory posi with brakes that doesn't need work, then it's a not a bad deal. But the value will be in it's condition. I've seen alot of rebuildable cores in the $1000 range. I found one for $800 that we put another $700 into and used the brakes (all new) from the 7.5. Comes down to how bad do you need one.

How much power are you making?

 

[marcar1993]

Idk, I think selling price and value are different. I have seen countless ones from $800-1200 for a 3.42/3.73 posi rear. I just picked up an 8.5, it was supposed to be a posi 3.73 (a little crusty, needs to be cleaned and painted) for $800. It was an open rear when I checked it out, payed $450 for it.
A friend of mine picked up a whole 85 442 rotted to pieces for $300, including the posi 8.5.

I didn't want to pay $450 for an open rear, but now I have a housing to put all new parts in. That's where it gets pricey.

 

[Ribbedroof]

Supply and demand. I have never seen a G body 8.5 rear for sale locally, and what they ask for Monte SS rears when one gets parted is comical

 

[LedSled]

I bought an 84' GN open rear for $750 south of Baltimore a few weeks ago. It was cleaned and painted. I'm rebuilding it with a new posi carrier, 3:73 gears, and powder coating. Also installing LS1 brakes.

 

[ssn696]

The 8.5 differential (including posi) from a Chevy pickup will drop in to the GN/442s one-legger housing, just need GN 28-spline axles to make it work. A $1200 'posi' is likely to be pretty used up at this point. Open it up and see what you are paying for before you buy.

 

[Slowpoke]

I bought mine freshly rebuilt with new internals from a guy that sells all kinds of rear ends and parts. 87 GN 8.5 3.42 posi for 1k. I think that was a lifetime deal.

 

[olds307 and 403]

Idk, I think selling price and value are different. I have seen countless ones from $800-1200 for a 3.42/3.73 posi rear. I just picked up an 8.5, it was supposed to be a posi 3.73 (a little crusty, needs to be cleaned and painted) for $800. It was an open rear when I checked it out, payed $450 for it.
A friend of mine picked up a whole 85 442 rotted to pieces for $300, including the posi 8.5.

I didn't want to pay $450 for an open rear, but now I have a housing to put all new parts in. That's where it gets pricey.

You got a very good deal. I would be lucky to find an empty housing for that price here. As I said, you probably could get away with a Lock Right but a good clutch posi is no doubt stronger and smoother.

 

[L67ss]

http://m.ebay.com/itm/370991931444


Would that work to adapt a non g body 8.5" to a g body?

 

[ssn696]

The whole reason Ford 9" axles work is that they are made of formed sheet steel, a design that dates back to the 1920s. Your EBay kit is a set of plates easily welded to a Ford housing. GM axles and later Ford axles typically used a cast iron center section with steel tubes pressed and plug-welded to the preheated iron pumpkin. You will not be able to weld upper control arm brackets to the cast housing. If you want to fab something, consider an 8.5 axle from an Extreme S10 Blazer, and rig up a torque arm like GM used on the Buick GNX. It used a special cover with mounting tabs for the torque arm, plus an Panhard bar to restrain the axle side-to-side.

 

[L67ss]

If google is correct mid 70s a bodies had 8.5" axles