doggonn

loking to purchace a posi unit for a 1965 cutlass 425 engine 355 gear ratio 8.2 rear . who makes the best posi rear ?

OLDSter Ralph

JDRace.com Jim is our resident rear differential expert. (330) 990-8155

66-3X2 442

The factory used cone type posi units. The best in my opinion is the Eaton style which is a aftermarket unit and is a clutch type unit.

doggonn

then go with a eaton? or is there other brands to stay away from or just as good as a eaton

66-3X2 442

I think Eaton is the only vendor for a 8.2 clutch type posi unit. Auburn Gear makes the cone type 8.2 posi unit. I like the clutch type units because they can be rebuilt and I think are just a better unit.

doggonn

thanks for the input . i think summitt sell eatons

66-3X2 442

I would search eBay for the Eaton unit. Sometimes there's a deal or two there.

doggonn

jim at jd race has a yukon dura grip posi any feed back on this rear and seller would be helpful

OLDSter Ralph

I haven't used the Yukon unit. Yukon is a brand name, but could be the "Eaton style" that 66-3X2 is referring to. I WILL be sending a 59-64 differential to Jim at JDRace for "Anti spin" (posi) installation.
66-3X2 is correct on the "cone type" not being as rugged..
Perhaps you can PM Monzaz on this site, that's Jim at JDRace.

11971four4two

I asked BOB Kelso about the yukon dura grip
basically same as 12 bolt chevelle
4 spring posi unit

I purchased one
have not installed it yet
LOL

monzaz

Yukon Dura Grip is a Eaton Posi unit made by Randys ring and pinion company.
When Eaton 30 year patent was up on the design other could copy it ....so he did.
We use them in all our rebuild and New builds.
Case is slightly thicker around the body , hardened spider gears, carbon fiber or composite clutches for smooth quiet operation, 400# preload spring for quick posi action.
We sell them in all 10 bolt and 12 bolt applications and even CUSTOM applications 9.3 Pontiac / Olds gasser and 12 bolt olds
Ring and pinion and rebuild kits.

Jim
J D

Fun71

Thanks Jim, that's some good information. When you say you use them in 12 bolt applications, do you mean O-Type 12 bolt or something else?

66-3X2 442

I think Randy's sells the modified Phord 8.8 unit for the 12 O Type. I could be wrong but that might be what he meant. Hopefully he will chime in.

monzaz

WE (J D Race) modify the Yukon 8.8 ford unit DURA GRIP for 8.8 ford. Yes.
Every one use to use the Actual FORD trac lock ford 28 spline unit to do this as it was the lowest cost unit on the market...BUT since the 28 spline unit is NO LONGER built from ford and none of the ford cars use 28 spline axles they have not built them for years. So the prices have gone up on all these conversion because the low cost original FORD units are Gone....