Hi,
construction guy here, definitely not a mechanic.
my gmc 3500 duramax started behaving differently today while towing my empty 18’ flatbed trailer.
the engine began extreme engine braking whenever my foot was off the gas and running at really high rpms when it normally shifts smoothly and quietly.
This is accompanied by what sounds like extreme fan noise.
it sounds like a diesel forklift or dump truck revving up to power hydraulic systems.
it’s making this engine noise even at lower rpms like 1200 and at slow speeds and highway speed.
I was travelling on my normal commute and regularly haul a trailer.
I’ve read the manual and can’t find any settings that change the behaviour and tow/haul mode doesn’t change the behaviour either.
started on the morning commute and was the same on the way home
anyone have any thoughts on this?
construction guy here, definitely not a mechanic.
my gmc 3500 duramax started behaving differently today while towing my empty 18’ flatbed trailer.
the engine began extreme engine braking whenever my foot was off the gas and running at really high rpms when it normally shifts smoothly and quietly.
This is accompanied by what sounds like extreme fan noise.
it sounds like a diesel forklift or dump truck revving up to power hydraulic systems.
it’s making this engine noise even at lower rpms like 1200 and at slow speeds and highway speed.
I was travelling on my normal commute and regularly haul a trailer.
I’ve read the manual and can’t find any settings that change the behaviour and tow/haul mode doesn’t change the behaviour either.
started on the morning commute and was the same on the way home
anyone have any thoughts on this?