GVRW is the total amount of weight the truck can handle including passengers and gear. The unladen weight of the '86 X-cab I have is listed at 3123. Figure maybe 100lbs more for the '85 do to the xtra weight of the axle housing. Here is a post on this topic Is my truck really this light? .

If your concerned about exceeding the trailers capacity, you can get your truck weighed at the county dumps, feed/hay store, or public scales(if in your area). The dumps is usually free, and the feed/hay stores tend to charge a few bucks(used to anyway).

More than tread lightly. Leave it like you were never there, nor anyone else.
'90 X-cab 4.88's 33 BFG AT's, rr ARB, Headers, Ignition upgrade, cold air induction.
'91 X-cab 5.29's 315's BFG MT's, rr ARB, custom bumper and flatbed