yes i have a 1989 gmc r3500 with a 454 tbi and i was wonderig how do i tell if its a high sierra , base or sierra classic? will upload pictures of it if they are needed.

i think you would know by looking at it, the upper models had a chrome words that said what it was on the cab post. the base model would not have much chrome and not say anything

Was just getting ready to answer your PM, but it looks like you already have the answer you need, hope that helps you get the right parts.

heres some pics of my old beat up truck.

pretty nice, crew cabs are pretty rare in that body style. what does that rectangle say behind the rear door

it says 3x3 i believe

one says 3+3 and the one ontop says sle sierra.what does that sle mean

thats normally where it is, maybe a base. there wasnt much difference in anything besides trim stuff like different accents inside or different chrome or no chrome. but i dont know specifically by looking at personally. the parts you have to use are going to me the same for engine, chassis, brakes and stuff. its all determined by gvwr if there is different parts at all

sle would be the trim package, sort of fancier trims

ok ty for all the info.just online parts site always asked and ive always wondered witch one