I have an 86 dodge d100. The truck only has 96,000 miles on the original slant 6. When I'm in gear, it's the automatic, and at a stop or very low speed it shakes and seems like it wants to die. Is it a compression issue and if so how do I make sure and then fix it?

After sitting for months, especially if it was not full when parked, it likely has water in gas tank. You can do a compression check also to make sure it's not a bad valve or rings

also check your vacumm lines. after time they begin to crack and proper air flow isn't going thru the carb.

My '78 Aspen was given to me for $300 by an old lady. Slant 6, 3-speed automatic.. it'd been parked under a carport for years. It ran rough, I believe only on 5 cylinders.. Had a bad miss. My buddy said it was a burnt valve. I never had a chance to check it out in depth because it ended up totalled.