78 rear axle ratio ??
 

I am trying to prove the rear axle ratio on my 78 1/2ton Silverado with out taking off the rear cover

the numbers on the pass/ side tube are KAS 229 W 8S

This is a stock 350 Auto that i have had since 78 and the numbers are not in the glove box that says anything about the rear axle ratio.

Ehere can I find this info, as I need it for the programmer on the LS computer!

Thanks Folks

Re: 78 rear axle ratio ??
 

Count the number of times the drive shaft spins to the rear wheel (jacked up of course)

Re: 78 rear axle ratio ??
 

Per the info packet in the GM Heritage Center archives (page 15 of the pdf; page 12 of the original):

http://www.gmheritagecenter.com/docs...olet-Truck.pdf

base axle is a 3.07. That assumes no one has changed it.

If you had an optional axle ratio it would appear on the SPID label.

K

Re: 78 rear axle ratio ??
 

It is not posi-trac!

Re: 78 rear axle ratio ??
 

Thanks, after many tests rotations, I think the 3:07 is accurate.

THANKS

Re: 78 rear axle ratio ??
 

After reading the Heartiage center doc. it said that a Heay Half, which is what this is, it says that it is a 3:40 !

Re: 78 rear axle ratio ??
 

The computer is programed fpt the 3:40 - 1, I guess i will live with this decision !!!

Thanks for the info