try it! if it's new enough (narrow enough) to fit between wheel wells, see if will fit with tailgate down. Had a 8' sixpac for our longbed ram, always pulled tailgate off when we mounted it----figured you had to. the guy i sold it to showed up in a shortbed chevy, opened tailgate & plopped it right in. Might not have bought my new longbed if i knew a 6' would work!