Another gearing question
 

I have a buddy that is giving me (if I want) the front and rear off of a 72 3/4 ton truck. He said its geared at 4:10. With a 700R4 and 33 inch tall tires, how would this be bombing down the freeway?

Re: Another gearing question
 

Perfect

Re: Another gearing question
 

Re: Another gearing question
 

like this:

Re: Another gearing question
 

Will be about about the same as a stock truck with 3.73 and stock 29" tires up to 3rd gear. Not accounting for extra rolling resistance and tire weight. Then will drop about 800 rpm going to 4th (overdrive). Should be fine. Nice thing about the 6l80-90 is there is an extra gear in-between 3rd and 6th. With 6th gear being fairly close to final overdrive of 700R4.

Re: Another gearing question
 

My K20 has 4.10s and close to 33" tires. It has spent very little time on the freeway, and that was years ago. IIRC, 70 mph was about 3000 rpm, so a 700R4's 70% reduction should yield about 2100 rpm. Which is in line with Jocko's chart above. Sounds about right for freeway use.