I'm trying to find out what I have under my 67, the casting code reads H118 but does that necessarily mean that its a 68 rear?? The axle code is CCA 08 15 W The only codes I can find that start with CCA are from 1970, is there some other code on it somewhere? What I have decoded using the internet is 308 open carrier made on 08/15 at Warren (anybody agree?) What about the year?Size 8.2 ??? Last for now, any opinions on Powertrax lock-right lockers from Richmond GearThanks, Jeff

 

[X(]Jeff according to my Chevrolet by the numbers book you are correct in what youve found so far. CCA is a rearend out of a 1970 chevelle or monte carlo, non posi, 3:08to 1 ratio. if a ten bolt rear its a 8.20 ring gear and if 12 bolt its the 8.875 ring gear. a note is included with this info about this axle also being used in some 65-69 models of the 116 in wheelbase wagons(chevelle) powertrax lock rights are a good option. the posi carriers tend to be a bit beefier than the stock open diffs that the lockrights are made for but i havent come across any that have grenaded although i dont think i would recommend for all out race applications hope this helps kurt

 

I work in a drivetrain shop, and I have seen a few lockright units fail, typically resulting in complete replacement of all internal components. I have installed alot of Auburn L/S and I'm impressed with thier construction. Also Thorsen and Detroit make clutchless helical gear L/S, thus eliminating the need for the friction modifier. I chose the Detroit Turtrac for my 79 Z.

 

I appreciate the info Kurt, also v8chyguy, I haven't had any problems with this rear but i'm tired of losing traction and burning one tire. I intend to go posi somehow, Jeff

 

[X(] i guess ones need for traction will have to be tempered by ones budget. as i said the stock and aftermarket posi carriers are stronger but will cost more besides the fact you then have to pay someone to install it. all this makes the lockrights an attractive option as you can do it yourself and the cost is less than a good aftermarket carrier. dont under any condition let someone sell or give you one of GM's gov-lock differentials. these are notorious for grenading and thus be costing you money in the long run. stock posi's are certainly a viable option, they have held up to big block punishment for lots of years now, you just need to know what to look for as you dont want a wore out piece of junk. you shouldnt have to pay more than $100-$150 for a used and functioning carrier(our local pick a part junkyard sells them for $60 when you can find one) these can be rebiult and can be set up tight or loose according to taste. only thing left is install costs with this option and shouldnt exceed 2-3 hrs at a local shop $100-$200 bucks which kinda puts it in the same range as the lockright (assuming the carrier doesnt need a rebuild) the carriers do come in different "series" and youll nee to be sure to find one with the same gear ratio as what you have or it wont work without other mods. the posi's characteristics are often found to be preferable to most people for cars that are driven alot(lockers tend to make noises and strange movements in the rear of the car, this is normal and just a characteristic of lockers) so i guess it will boil down to budget and personal preference hope it all helps kurt

 

The problem is that the Lockrite unit opperates on the same principal as GM's Govloc only, it locks up as soon as torque is applied. the Govloc needs to see a 300rpm speed difference before it locks. Govloc has a cam follower type sidegear that cams out when activated forcing the sidegears together, effectively locking the carrier. the lockrite uses two sideclutches and two driven clutches that cam off the crosspin. what fails in these is the driven clutches, the crosspin mushrooms the the cam slot and the driven clutches begin to break apart. It's those peices that do most of the damage. the other, more extreme failure, is caused by the force applied to the carrier. Litteraly splitting the carrier in half. This pic is of a GM 8.5 10 bolt Govloc. It was replaced with an Auburn LS unit.