I just love it when the Service Writer tells me I have to drive it at 2200 RPM. which can only be done on the automatic if I drop into manual shift. As the automatic will drive all day at 60 MPH @ 1400 RPM. According to Cummins the engine was designed to run at 1400 RPM for maximum fuel efficiency. I have over 100,000 miles on a stock 6.7, however I can tell you the EGR, CAT and DPF are about to have an accident and fall off the truck so the engine can breath pure air and get rid of all the once burned soot out the tail pipe. I run anywhere up to 12-14 hours per day at highway speeds and the only time I have ANY trouble is when I have to run around town, this truck just is not set up to run around with city folk. lol
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2007 6.7 L, 2500 QC, Laramie, SB, 3.42, Mag-Hytec, 68RFE, Harvard 156L Bypass Oil Filter, Patriot Blue, 4X2, Michelin LTX Summer, Nokian Hakkapelitta Winter, Roll-n-Lock, HERD Bumper, Espar Cab Heater, Sirius, AY Reflash, SS636, 5050XL, PMT, Have Truck, Will Travel