That usually has nothing to do with a truck skin.
You sure you are above Level 5 for the trailer purchase?
Some economy mods due to a minor mod conflict enable the purchase of trailers before the game actually is supposed to. That threshold is Level 5.
If done before that the game crashes as soon as the player hits "purchase".

because the gam crash every time i put on any upgrade

can u not put upgrades on the trailer

Awesome thanks man :)

will work on these

very nice work,its needs to added to the new mack also please

Looks awesome.Thank you for your work.

Any chance you could add the PB to the truck list this covers? And maybe add Ken Blocks 43 number as an option :p Haven't downloaded it so if it does work with the PB my bad, I see it in the pics, but in the description it doesn't list it