Why not a 2 speed or quick change rear end option

wilber1 wrote:
Word has it the clutch design of the Gear Venders does not stand up well to exhaust break use.

That is correct. It does not like "reverse" torque, so you cannot engine brake while the GV is in its OD gear. Should be easy to connect the EB signal to disengage the GV, so you'd also get the benefit of lower gearing while engine braking.