C1 Rear axle terminology

[Christer Arakangas]

Hi,

I am about to buy restoration parts for my solid rear axle. Since I am not an experienced mechanic or restorer, I am somewhat confused regarding the terminology used.

Can anyone explain to med if I have a 7 1/2", 7 5/8", 8" or 8 1/2" and 10 or 12 bolt rear axle, or what? I apparently need to know this to be able to buy parts.

Thanks,

Christer

[Dennis A.]

Re: C1 Rear axle terminology

Christer...

Not knowing what parts you plan to buy, C1 axles are either Positraction or Non-Posti. You will need to identify the gear ratio if you plan to replace gears. Rear End rebuild kits are are available, but you better have the proper tools. If you are replacing the bearings and O-ring seals, you might want to buy these from a Vette supply house that will provide the correct bearing by the year of your car. Also Identifying the casting numbers will get you on the right path.

[Joe Pennington]

Re: C1 Rear axle terminology

The C1 has a 8.2" (diameter of the ring gear) 10 bolt ( # of bolts that attach the ring gear, and normally the # of bolts that either bolt the rear gear assembly to the housing, or the number of bolts that hold the cover plate to the housing, on later style units). Other GM units, newer models where the axles are retained using C-clips, also use a 8.2" and a 10 bolt rear but are not interchangable with the earier design used in the 56-62 vette and 55-64 full size chevy.