I think the E.G.R. valve has gone.
The valve cover gasket leaks.
Sometimes idles out of control. (4000RPM's!!!).
Rust down low on the quarters and fenders.
The tail gate doesn't close easily.
Front left leaf spring sags.
Sometimes hesitates under acceleration.
This truck is awesome. It goes anywhere. The steering is like a car. Just put in new platinum plugs. This thing is as tough as a tank on steroids. 4x4 shift on the fly is great. The posi in the back is awesome. It has a plow and boy does it plow.
I have almost the same exact problems as you did. My 1988 Ramcharger is 318 3speed w/granny gear. It's great Off-road, I've put a lot of money into the truck, but it worth it all. I'm not worried about the looks, If the engine doesn't work right whats the point of it looking good. I'm saving now for a 8" lift. I'll have enough this summer then I'm going to hit the big trails. Plans for tires are Super Swamper Boggers.
My 1979 dodge ramcharger has a similar acceleration problem. The funny thing is that when in town the truck run at about 40%, but put her in four low and she runs at about 60%. I have yet to get the beast stuck running bad I still can't get it stuck. I LOVE MY TRUCK. If you have a ramcharger, it may suck gas like no tomorrow, but keep it you won't regret it come winter. That truck can make you so much money in the winter time it will practically pay for it's self and repairs.
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