What happened and did it cause damage? ?

I recently got a new to me truck, gas GMC 2500hd (with towing package). Today I bought a dump trailer (4500lb) and was taking it home. I had the tow mode on but stopped shut the truck off and forgot to put it back on. I was then going up a hill and was going about 25/30mph and realized it was alittle slow and wanted to see how it could pull. Slowly started applying some gas but nothing was changing so I applied more very evenly and then all of a sudden it jumped up to high RPM maybe around 4500k-5000k at which point I slowed back down. Is this normal? And could it have done any damage to the engine or transmission? I will be making sure it’s in tow mode from now on. Thanks 

1 Answer

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  • CB
    Lv 7
    1 month ago

    No harm no foul, you just woke up the transmission enough to shift down. Towing mode just changes the shift points letting it use lower gears longer and shifting down using certain criteria.

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