57 chevy posi rear with GM 5.13 gears?

i have a 57 chevy 3rd member thats a posi and has 5.13 gears with a GM part number on them..... is it possible that this came from the factory this way???? or could you buy 5.13 gears from GM?????

 

I have a set of 5.13's for my 409 biscayne. I just haven't put them in yet. Gas is bad enough with dual quads and 3.336's. I have even heard of some 6?? somethings for this rearend. Real stump pullers.

 

maybe powerglide cars? dont quote me but it would make sense?

 

do the chevy trucks rears use the same gears?????
maybe some one ordered a 57 fuelie with these gears??? hahaha... that'd be cool.....

 

5.13's were available for the '55-'64 Hotchkiss 10 Bolts over the counter through Chevrolet and may have been dealer installed.

 

Ahhhh, the glory days...............

 

Optional gears OTC from the factory. Remember--factory backed racers didn't have to buy a lot of stuff on their own.

-Brad

 

The 46-64 chevy parts book lists 5.13 and 5.38 gears, 2 different numbers for 3 or 4 series carriers for each ratio.

3830266, ...69, ...71, ...74 are the part numbers.

 

the rear diff wasn't a p***enger car housing with 6 bolt axles, was it???

 

no it was under my old 55 chevy.... and had 5 lug wheels...

thanks for all the help...... im thinking the gears were bought from the parts counter and put in......