It's a 1998 5.2L (older version with a regular old style radiator).


If your overheating with the T-stat out then there is defiantly an issue. I would first assume because you overheated the motor that the head gasket is gone, however I would replace the water pump again with a NEW one not a rebuild first it a pressure test good, there is no steam in the exhaust, no antifreeze in the oil, no oil in the antifreeze, and no oil in the exhaust.

Could also be a radiator.

 

thanks for all the reply guys, much appreciated for all the info.

Sog some supplies during the day unfortunetaly I pickecd up wrong trans filter kit so that was no go. For my engine they had 12 or 15 bolt pan kit listed. Well for some odd reason my pan has 14 bolts in it, was going to pull the pan out and just make a new gasket with black RTV for better oli resistant but only had gray on the tool box. So that was no go and my oil poddle on the driveway is getting bigger. Will have to go directly to dealer and pick one up tomorrow.

Any way, checked the trans oil again cold not runnig. still safe zone but rather on lower porstion (darn trans leak ) Started engine and check it in neutral with in a minute or running. Dipstick went dry. Added about quart and half before it got to mid level in safe zone (darn it trans leak)

Replaced engine oil and filter) not sure exactly when the engine oil was replaced but it was on the darker size and kinda smelled stale and as if it had some exhaust small in it. First thought, head gasket second thought piston rings or valve seals.
Now I definetaly need to do compression and leak test, cause if its either one I'm out for either head gasket replacement or worse engine rebuild.
No coolant in drained oil and no oil in coolant, so it seems like that the head gasket might be ruled out.

After putting new filter and refiling engine block with new oil, started it in neutral and left it running for about 10 minutes. temp was roughly at about 65'c/150'f Figured its safe and decided to go for a drive. drove around the neighborhood (lots of stop signs) to simulate stop and go traffic with heater on. temp climed to about 80'c/180'f after about 5 minutes. Turned heater off and temp climed to about 95'c/205'f after additional 10 minutes. Bit hight but not terribly bad. decided to go on highway, temp stayed almost looked like it droped degree or 2. Turned around and got off the higway, back on city streets few stop lights. Temp started climbing to about 110'c/230'f. This is definetaly not a good sign, engine did not overheat yet or anything, just did not liked the rising temp.
This is all still with the t.stat out and air temp at around 10'c/45'f. Just wondering how bad it would get in mid summer with AC running.

long story short, I'm still looking into fixing trans leak/ replacing filter in it and replacing the oil. Just so that I can have my driveway dry but now with huge oil spot on it.
Have to do cylinder compression/leak test, but will have to take it to shop or dealer as I dont have the tools to do that, unless someone is willing to lend it to me as exchange for cool brewskie .

I'm also looking at replacing the water pump and/or radiator as hydrashoker has sugested. Not to disagree but the water pump seemed like excelant quality pump with machined mating surfaces and very good looking fins on the propeller. and it seems like its working cause I get lots of heat during the winter and still now up here in Toronto and the rad hoses seem to be hard/full when engine is running. Still not ruling it out.

so thats it for tonight and still pived of about the problem.

 

hey guys, I hate leaving things open and not coming out with conclusion to the subject.

Any who, moral of the story is, I got my self a new rad with extra trans cooler being that the one in the truck was still OEM and had very little or almost no flush in it so it was logical choice.

Replaced it and driving now for almost 2 months now with no over heating. At the same time that the rad was out I dropped pan from the trans and put new gasket in and had not a drop from it yet.

So knock on wood, it will hold for long time.

Again thanks to everyone for their comments and help, very much appreciated.


On side note, old rad I had it drained and trying for about 2 weeks before it stopped ripping. I guess there was huge amount of deposit in the fins that was holding fluid in and not passing through hence my o/h problem

 

thanks for the update man, glad to hear you got the problem figured out

 

: ) good you fixed that!