is it comming from outside the cab, or inside, mine makes that sound too, but it is definitely the spedo cable, and it only does it in cold weather. I did have a big truck that made that sound one time, accompanied by a vibration, this was about 50 miles before the ring gear in the rear drive axle snapped in 3 pieces, i hope that is not your problem.
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"In the words of Motley Crue, This will always be my home sweet home"
Ol' Buck: '72 Chevy 1/2T 4x4 shortbox stepside 350/350auto on '84
ralleys and 31/10.5s
Angel girl: 67 Cutlass convertible
330, 3spd stick
Greener: 90 GMC Jimmy
350/auto
Chad Stephens
Orleans,NE
no name yet: 72 442 under serious construction
my site:
http://communities.msn.com/Beastonabudget/homepage