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Mile_High's avatar
Mile_High
Explorer
Apr 12, 2016

Chipped 450 Cummins

Anyone chip their Cummins diesel? I looked at a guys Class A and it said 550 where it should say 450, and he said it's chipped because he hauled a trailer. 39K miles on the odometer.

Is that a "run away from the deal" or is that pretty common practice?
Class A
  • Ivylog's avatar
    Ivylog
    Explorer III
    Apr 13, 2016
    Run, the Allison 3000 tranny is maxed out at 400 HP... 1200 ft lbs max. The ISL 450 has a flat torque curve from 1200 to 1600 rpms to not over work the tranny.
  • Tom_Barb's avatar
    Tom_Barb
    Explorer
    Apr 12, 2016
    We have a Banks intake and exhaust kit and a programer on the 8.3 / 350. over the past 48k we have put on the coach it has averaged 9 MPG.
    This last trip we ran 65-70 up I-15/ I-84 it didn't seem to make a big difference to fuel millage. that tank gave us 8.mpg, but we didn't do 65-70 for the whole tank.
    Yes, we do keep a log of the fuel we buy.

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