Ive had this 6.2 truck for a few months now, and something new happened today. To start off with, when I first got it I had to repair a leak in the radiator overflow tank, then I topped it all off with antifreeze, but when Id run it, it would spit some out the overflow of the overflow tank even when the engine was cold, like it was overfilled. The other day the low coolant light flashed on for a split second then went off, so when I got home I looked and the coolant level in the radiator was just below my lines to the heater core. I thought the cap was bad because it spit that coolant out at low temps, so I put a new cap on and filled up the radiator, but the overflow tank still was near the full mark. I go to get in it today, start it, drive it 10-15 minutes of easy driving just to get it up to normal operating temp, when I stop the right exhaust(true duals) is smoking white at idle, not heavily but still smoking. never done that before. I let it idle for a few seconds, got a little better. On the way home at driving RPM's it never smoked a bit, stopped and let it idle, only a tiny amount of white smoke, when i revved it up to pull out it smoked a little more, but still not as much as the first time. Now its definately possible I overfilled the cooling system, but would that do that? also it has a rough idle now, but not too bad, just barely noticeable. power seems the same as usual. did I blow a headgasket or what happened? It hasnt cooled down enough for me to check the coolant level in the radiator. The overheating warning light has never came on, and the bulb is good. Any help is appreciated.

Sounds like all the symptoms of a blown head gasket, or worse cracked head. Both common problems with these engines.

What does the smoke smell like? It will smell just like burnt coolant if thats what it is.
If its sour and burns your eyes then its diesel fuel, if its sweet smelling thats oil.

Odds are, since its just one bank that seem to have the problem, it is a head/head gasket problem. Your best bet is to pull both heads and inspect them for cracks and replace both gaskets.

I went out and started it again. at first it was all blue smoke out of the right side, smelled like diesel exhaust, but the longer the truck ran, it turned to white and smelled like burning antifreeze, before i started it this time I checked the radiator which was full, it was almost empty. I know where I can get a good 6.2 for cheap, guess I can go that route.

All you need to do is replace the head gaskets, I don't think you need to replace the motor. Pull the heads off, like TDG said check for cracks, clean the surfaces up, get new head bolts and Fel-Pro head gaskets and put it back together.

ok, that 6.2 I mentioned earlier, the heads are good but the block is bad. Most likely if I need anything other than gaskets it will be the head itself, but that is an 86 motor, and mine is an 82. The guy told me the 86 heads will bolt up to the 82 motor, but something about the injector lines are different. Is that right? Would those be J code heads, and if so, would they add any power? Im thinking thats the cheapest route to go, because hes willing to give me that whole motor, injection pump and a complete new gasket set for $75, sounds dirt cheap to me but I have dealt with him before several times in the past.

Heads will bolt right up no problem but, the injectors will be different. 'C' and 'J' code engines are the same heads. Difference is the injection pump calibration and EGR valve.

You're '82 will have the coarse thread long body injectors, the '86 will have fine thread long body injectors so make sure you get the injectors with the heads.

High pressure lines will be the same, injection pump will be different but either one would work.

I strongly reccommend taking all 4 heads to a machine shop and have them all checked out and get new valve guides and such while its in there.

Odds are that they will find you 2 good ones and 2 cracked ones, but if they're all good then you can sell the other pair pretty easy, people are always needing them.

Well Im about ready to start taking it apart to see what I find. I took the injectors out of the right head and cranked it, antifreeze shot out of the injector hole second to the front of the head. put them back in and ran it enough to move it from my yard to the garage (20 feet) so I can work on it. Took a bunch of pics of the engine so Ill know what goes where when I reassemble it. I just hope the head is still ok.

It is very good that you know which cylinder is eating the coolant. Try to limit your initial inspection to that cylinder, ie cracks on head in that cylinder, cracks in cylinder wall of that cylinder, head gasket failure on that cylinder. Due to the fact that 6.2 heads are prone to cracking between the valves, look for traces of coolant if you find cracks. If you find cracks with no signs of coolant, that is probably not your problem. Most cracks between valves on 6.2/6.5 don't leak coolant or combustion, but it is best to pressure test the heads to be sure, but don't throw away heads just due to cracks between valves. Leaking cracks can also be repaired by a machine shop by reaming the coolant runner and pressing in a bronze valve guide to seal the hole.;)

I started tearing it apart yesterday, I have everything taken off and unbolted that I need to, The head bolts are out and Im ready to take the head off to replace the gasket. Problem is, the head seems to be stuck really good to the block. I took a 3 foot prybar and pryed between the exhaust manifold and frame, and it just twists the whole motor/tranny/t-case in the mounts. the head doesnt budge. Yes I unbolted the exhaust pipe from the manifold. Im afraid of using too much more force, dont wanna break something. Any ideas?

You are prying up not sideway's right. There are guides in there that the head sits down on. Just making sure.

Yea I was prying straight up. It acts like its still bolted down but I took all the bolts out, think there was 16 of em. I dont want to try to drive something between the head and the block and mess up the mating surface of them, that would make a leak when its all put back together.

Ok finally got it to come off. Cylinder head looks good, no cracks at all...old gasket looks like crap. It appears from looking at it, that the gases in one cylinder had been leaking over, or blowing over into the cylinder beside it via the bad head gasket. Looked like all 4 cylinders had been doing that, then it finally leaked enough where it got into the water jacket in one spot. I may be wrong, just going from what i saw.

Would you mind sharing with us what method finally broke apart the head from the block?

Sure. Probably not the best or smartest way but it worked this time. Took a 1/2" drive breaker bar handle and stuck it in the water jacket where the coolant crossover pipe bolts to the head, pulled torward the passenger fender and it broke loose with some force.