Shimmy in front end
2004 chevy 2500 cargo van,shimmy starts at about 50 mph, gets kind of severe then at 55 mph and above goes away.
Couple things come to mind, tires belts shifted, wheel balance, alignment. loose/worn suspension components. Any uneven wear or cupping that you can see on the tires?
Search Chevrolet Express Cargo Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Chevrolet Express Cargo Experts