I'm in the market for a new truck and have decided on a Chev or GMC with a DMAX. I'm not sure if I want to shell out the extra 2300 for the Allison. How does the 6 speed perform? I know the allison has the grade braking feature, but could this not be accomplished by manually shifting the 6 speed? 2300 clams can add a lot of other bell and whistles. Any thoughts...

Thanks in advance for any feedback..


Ron