* Check the owner's manual: This is the most reliable source.
* Look at the vehicle's specifications sticker: This sticker is usually located on the driver's side doorjamb.
* Use a reliable online resource: Websites like Edmunds or Kelley Blue Book often provide detailed specifications, but you'll need the exact trim level and wheelbase of your van.
Without knowing the specific configuration of your 2010 Chevrolet Express, providing an exact rear track width is impossible.