The truck model went from a 1979 GMC to 1986 3/4 ton 2500 longbed models, the GMC trucks was Sierra Grande and some Sierra Classic, in the Pilot "Fall Guy, Part 1 &2" the truck is a 1979 Sierra with round head lights, ( You can notice this in the opening credits when the truck jumps through the glass.)
Latter during the show run they went from round head lights to square head lights with the turn signals now in the front bumper, in the pilot episode Colt's truck doesn't have the hood decal on though, reason is the truck at that time was done being built so after that they finish it up by putting the hood logo on it.
the truck was a 4x4 with a 4 inch lift under it.
They went through alot of '70s an '80's models 1/2 ton to 3/4 ton trucks for the show.
Both Chevrolets and GMCs was stunt models for the show, they also used a short bed truck in the episode Trauma.
1'st show 11/4/1981 last show 5/2/1986
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