A thump noise every time I stop or take off
Every time I hit a bump or quick
stop or ready to drive off or slow
down and then take off again
my hummer makes a loud
thump noise like as if the axle is
loose. The n when Im in park
switching to reverse or drive, the
gear feels a little stiff.
Possibly a bad motor mount or transmission mount.
More likely your driveshaft slip-joint needs to be lubricated; as you go from Park or Drive to Reverse, the axle winds in the opposite direction and the slip-joint needs to slide. If it's sticky, it resists then lets go suddenly causing the Thump noise.
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