1200-1400 is noramil for a stuck truck under a load such as a headwind. 300* for cool down would be more than adequate but 350* is plenty safe on these new turbos. Plus, 350* will save you a bunch on idle cool down time.

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'08 Ram 3500, QC, DRW, 4x4, 6.7L, 68RFE, Laramie ~ H&S XRT, Edge Race J/A, B&G "Modified" TCM, Goerend Twin Disc, X-Monitor, ARP 625's at 160, GDP MODS: Air-Boss 67 Grid Delete, Arctic-Heat Grid Reloc Kit, Pro-Gate 38 (open dump), Full Flow EGR/Cooler Delete, Maximizer Big Line Kit, Double-X Ladder Bars, High Output In-Tank Pump Mod in the works...

Richard @ GDP
509-993-4923
Glacier Diesel Power.com