Hmmmmm.... yeah I was playing 2fort today and noticed the pickup trucks off to the sides in the blu and red courtyards. They both looked perfectly fine. I had tried using an info_lighting on it, which helped, but just made it look like dim mirrors rather than shiny mirrors. I'll have to grab a decompiled 2fort file and see if I can figure out what they did. I'd already done a search on this site for related threads and came up empty.
EDIT: I'm just getting to a point in my first map where I'm finding weird lighting issues and trying to solve them, and this is just one of several. So, I'm in a learning stage here... hopefully I'll figure it all out
EDIT EDIT: Okay, a little more sleuthing turned up the thread you'd mentioned, where it was suggested to try a path_track and/or an info_target rather than an info_lighting. Furthermore, examining the decompiled 2fort map showed nothing unusual at all. They had set the model to no physics (makes sense, as it's outside the play area) and put a fade distance on it. Otherwise, all default settings with no lighting source designated. So I made a little room with no lighting in it at all, pitch black inside, put a path_track and an info_target inside AND outside. I didn't think it'd make any difference, but for the sake of completeness, I made different blue pickups that had fade distances set, default physics, no physics, and using the bounding box for collision. I set each one to use one of the different entities for their lighting source. No effect at all, all models were lit the same and had the same reflective surface all over. I CAN get it to where the reflections aren't very noticeable. From some angles it'll look okay, but the reflections are still there, and if you just move a bit it'll be all shiny wood and tires again. I have no idea, at this point, how Valve got theirs to look normal. Oh, and yes I'm using cubemap entities and building the cubemaps.
So... if anyone can give me a hint, or at least confirm that I'm not stupid/crazy/completely clueless, that'd be great... otherwise, I guess I'm only using the red pickup for now. It's more of the puzzle of the thing that's got me, rather than the inconvenience of not having the colour skin I'd prefer.