I agree with Bmac, I also follow the 5 minute rule on my rig. Cummins warns against idling for more than 10 mins but I cut that in half just to be safe.
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2001.5 White 2500 Reg-cab • 4x4 • NV4500 • 4.10 • BHAF • WALBRO GSL392 • Edge Juice + Attitude • VALAIR HD OFE • Scangauge II • 315 Cooper S/T's • Optimas • custom black grille & blue graphics • ** Diesel Fuel Treatment is here **