In my opinion, if you are planning to buy a 1980-1989 Dodge Ram 50 truck, have a mechanic check out the vehicle before you sign anything. I just recently bought a 1987 Dodge Ram 50 truck. It has a 2.6 liter, 4 cylinder engine and a 5 speed transmission. After I purchased the vehicle, I started noticing white smoke coming out of the tailpipe at a pretty constant rate. The dealer agreed to replace the head gasket and mill the head to see if that would fix the problem of my engine coolant getting into the piston chambers. When I got my truck back, I found out that the head was not the problem. The block (engine) was warped in my truck. I talked to the dealer and he said he would give me my $ back. I decided to go car searching, and found 5 other Dodge Ram 50 pickups around my same year with engine or carburetor problems.
You see, mid 1980's Ram 50 trucks' engines are made by Mitsubishi and imported for Dodge. I have determined that these engines and carburetors do not like lasting for very much over 130,000 miles. The body, rear end, and everything else lasts fine, but not commonly the engine or carb. Be sure to have this type of truck inspected before you buy it, because you have very good chances of picking up a dead pickup.