2000gmc Sonoma sls 2wd
I have a 2000 GMC Sonoma step side.
And recently I've noticed a humming
sound that's gets loud then quiet
almost like a wheel bearing going out. It
only does it consistently when cruising
at 55-58mph. And the rpm jump a hair
when the humming is happening. The
rpms go up with the humming and
down to normal when it quiets. Truck
runs and shifts perfect. Few people
think it has something to do with the
power train but are confused to what it
could be with it running so well... Any
answers would be great!!