Hey need help!!! Me and a buddy of mine both have 89 Dodges with Cummins's and automatics, and both of our trucks are getting hot. These trucks have been drivin on 105 degree days without the temp. guage moving off the cold mark, which is why this is unusual. Both trucks start cooling down if your going around 65 m.p.h., but otherwise they start heatin up quick. I also smell antifreeze from mine when i'm going down the road but there is no signs of leaks of it anywhere. There are no smells of anything from my buddys truck. Thought it could be headgasket, but why would cool down goin down the road if it were? Both of these trucks also act like they want to cut off sittin at stop lights in gear too, the oil press. drops to 2 lines and idle drops way down like its not getting fuel. My truck has 237k miles on it and his has 243k on it. Another friend of ours has a 90 Cummins with a 5spd and close to same milage and doesn't have any of these problems! We also own 3 92' Cummins's none of which have ever had any problems either. If anyone knows anything about what could be wrong of these two trucks or whether its the same problems, please help. These trucks have a lot of life left in em.(hopefully)

 

check the construction of the radiator, a friend had the same thing with his '89... he found the inlet was on the same side as the outlet, he took it to a radiator shop and they put a new tank with the outlet on the other side on, it cured his over heating problems... i guess dodge made a bunch of them that way.
most guys will just let it go because they don't pull or haul enough to bother them....hope this helps..... let me know

 

are you getting proper heat from your vents?