I was fueling up last week when another dmax pulled up to the next pump. We began swapping stories and he mentioned he worked for a company that sold the medium duty allison transmissions. He then told me that an allison tech guy told him that the origional 5 speed allison 1000's used from 2001-2005 had all of the hardware to make them 6 speeds, it was only a slight electrical mod. Is this true or is he full of crap?
Thanks!!