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Travel_glampers's avatar
Travel_glampers
Explorer
Feb 06, 2020

2009 Silverado 3500 HD Duramax LMM overheating

I have the above truck towing a 14,000 pound fifth wheel. When the truck was new, it overheated going up to Eisenhower Tunnel (11.000+ feet) in June. Both the engine and transmission (Allison) tempe...
Tow Vehicles
ScottG's avatar
ScottG
Nomad
Feb 06, 2020
That was a common (and real) issue back then but yes, there are mods to make it better, although it may not totally solve the problem.
GM made changes a year or two later that took care of it.

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