What would cause the truck to constantly drift side to side in your lane while driving down the highway? I can't seem to keep the truck in a straight line anymore. Either my driving skills are going bad, or something in the truck is wearing out. I'm just over 65,000 miles on the 3500 SRW LB. Ball Joints? I have the 100,000 extended warranty and have a list of things to get fixed already. I just want to have an idea what would cause this before I go before the service manager to plead my case to get it fixed...