On to the direction I am going with this. I am comparing by my observations the situations that I seem to come across classic trucks from the big three.
Chevy- I seem to come across these always in the middle of a resto or customization either lowered or on monster size tires. They seem to be the easiest to get custom parts for 67-pretty much now than any other truck I have ever seen. So much that I being a Ford guy have owned a 71 once. I usually see them going for higher prices than I would pay for them. Completed trucks tend to have an insane price. Pretty much the truck version of the Comaro when it comes to popularity.
GMC- I realize that GMC and Chevy share a lot even from the same parent company. But from what I have seen of these from 67-at least the early 80's the GMC is the better of the two trucks. I find GMC's to be a lot rarer than the Chevys. When you find one that maybe worthy of resto or modding the owners want cazy prices for them. If you find a late 70's long bed you have hit pay dirt. I know a 77 GMC truck has been passed down through my family everybody wants the dang thing to include me. Most of these seem to be gone due to them being used as what they where marketed for (work trucks) or bad body rust.
Dodge- Most I find have been sitting in the junkyards so long they are not worth touching. I don't know what mopar parts go for these days but I know they use to be expensive back in the day. Where I am from the mechanics circle I ran is had a saying "You can build 2 chevy engines and a ford engine all together for what it would cost you to build a dodge" I have rarely seen a classic dodge on the street. Truck that is. Heck I cant tell the difference between a late 70's Dodge and a early 90's Dodge. I have come across a late 50's panel truck I want though.
Ford- My favorite of all trucks I still see so many classic f-100/F150's around. A lot are still on the job. I know a few farmers that just wont give up their old Ford farm trucks. I have learned these trucks are tough as nails. My best friend has a 70 short bed that use to be his grandfathers work truck when he use to be in the logging business. The old 302 is still in the truck and working just fine. When I come across these trucks they are usually not to expensive and are still running with original gear in them. My first vehicle was a 72 long bed that my dad bought in 78. I know what that truck went through. I never have seen another truck other than F-100's that could be loaded so much that the bumper is almost on the ground as often as these and still keep on working. Now I am lumping in the Mercury M-100's with the Fords because from what I have heard is they are pretty much the same truck and I have never actually seen a M-100 in person. I would love to have one though. I think the F-100's/F-150's are the easiest to get for a decent price and not be a complete wreck. Yest they cost more to lower or raise if you have a 2wd but I think its worth it and from my experience the old Twin I Beam suspension is a rock solid set up. (ok so I might be a little biased when it comes to classic trucks)
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I really don't know what started me on this post but there it is. These are just my observations. I could be completely wrong. I take criticism well.
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Logan