Originally Posted by CONNARD

Chewwie, it's almost impossible to diagnose an egine problem on the internet but if I'm understanding you right, the truck rolls when it is at idle. If this is happening then it is one of three problems.
1 bad clutch bearings
2 a weak or broken clutch spring
3 a sticking clutch shoe ( this happens alot with alluminum shoes. just take them off and file a slight 45* angle on the outsides of the shoe. hope this helps.