Climbing in the Rockies
Have a question. I have a 3500 GMC diesel. My question I when in the mountain areas should I leave it in drive and use the exhaust brake, or put it in manual and shift gears when climbing and descend...
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Have a 2015 GMC 3500 Duramax. Have made 4 trips through the Bighorns, Yellowstone, Glacier, RMP. All pulling a 12,000# TT. Never once took it out of Drive/tow-haul with exhaust brake on. Very seldom had to touch the brake pedal. It works as designed if you let it.
