After all that I have done with the Allison I may still take yet another turn. I found a Brown-Lip three speed auxiliary transmission with an under, direct, and an overdrive. This transmission originally came out of a little dump truck like mine. I am not sure yet I may put it behind the Allison but have a GM NP435 4 speed that I may use with the Brownie. Either way I will have the overdrive that I need, with the 435 it would make a true 12 speed or if I started with the 2 speed rear in low and shifted it to high after going thue the two transmissions it would be a 13 speed. Not sure about split shifting the Allison I think I would just use direct to get going and after the Allison hit 4th I would shift to overdrive making it a 5 speed the under drive would just be use for a low crawl speed. If I use the NP435 I will put the Allison in my 71 1 ton that I want to put a service body on and use for lube fuel and repair.
Last edited by HevyHauler; 05/07/2008 11:01 PM.
