ALLISON REPROGRAM W/DPF SYSTEM

[LEAH DRAPER]

Gerald
Am getting more interested in having my 2008, C9(425) with Allison reprogrammed to 6th gear.  However I have the engine/exhaust brake rather than the Jake.  To your knowledge, do you think with the DPF system that would cause any problems?
Leah

[Gerald Farris]

The reprogram to 6th should cause you no problems with the exception of the fact that you will have diminished engine braking with the engine at lower RPMs. The coach design engineers chose the lower gear in the original programming to give you a higher level of engine braking when the exhaust brake is activated. With the transmission in 6th gear the engine will be turning so slow that the braking effect will be diminished greatly with your system design.

The bottom line is that it will cause you no problems other that the need for more driver input into the proper gear selection to get the desired engine braking. However it will also give you the benefit of not choosing to gear down and use less engine braking for those long gradual descending hills.

Gerald