Recently purchased this truck, so not a lot of history to go on. Noticed the truck ran a little warm, and the coolant was brown, so I had it flushed. Also replaced to rad cap, and the thermostat. Thought I might have had air in the system, so I ran it in the driveway with the cap off and filling it as it seemed to burp out. The fan clutch was also shot, so I replaced that last night. I have noticed since day one I hear a gurgling sound whenever I accelerate. Now that I replaced the clutch, it straight up over heated on me this morning. I'm at my wits end. I see no drainage anywhere, and changed the oil over the weekend to check for coolant in the pan - nothing. Did I go about it the wrong way when I burped the system? Is that gurgling noise trapped air in the line? Am I missing something else entirely? The heat works just fine...so I don't think I'm looking at a plugged core. Plugged radiator, despite the flush? I know, a lot of info and questions. Any input in helping me get to the bottom of this would be appreciated.

When I had the cap off and was filling I could see coolant cascading in the radiator, so I assume this to be a sign that the water pump is in working order...

 

I would try burping it again, only this time, use a floorjack to lift the front passenger side of the truck nice and high, then run it with the radiator cap off. That should help get the remaining air pockets out, while filling it up with coolant as you go along. That's the method I used, and I have never had a problem with it.

I would assume the water pump is good since you said you could see the coolant moving around in the radiator. As long as it isn't leaking out of the weep hole, it should be ok.

Good luck!

 

Update: Still overheating. Grabbed a waterpump on the way home. Had the heat running to try to help alleviate the heat in the engine. I popped out of the truck when I got home to check for collapsed hoses while it was running at a high temp, and found the compressor was sweating like crazy, and ice cold to the touch. I had not been running the AC. Possible sign of something else?

 

was it on defrost? if so the ac was still running

 

No...the compressor motor is cycling on and off of it's own accord. No matter...I pulled the fuse to it and I'm still at square one. It runs ok and at temp for about 12 miles, which coincidentally is right about where I get off the highway and drop off to about 35 mph with some stop and go. At this point it creeps to an eventual overheating condition. It was just running warm until I replaced the fan clutch...and I'm curious if I may have installed the fan blades backwards and if this is now part of the problem? Hell if I know...this is really starting to **** me off. I did discover last night after I swapped out the water pump that I might be spitting a tiny amount of coolant out the tailpipe...whether or not that is a new development I'm unsure of, but I assume that would mean the lower intake gaskets are in need of replacement??? I am about ready to toss in the towel and just pay someone to figure it out...

 

I see you replaced the thermostat. Something I've started doing is drilling an 1/8" hole which allows trapped air to get past and a small amount of circulation even with the thermostat closed.
I would suggest pulling the top guard to the radiator and checking for bugs/leaves between the condensor and radiator. Also look at the front of the condensor and see how damaged it is from rocks/etc.
If all that fails you could be looking at an air/fuel/ignition issue as the cause. It should not take a lot to keep a correctly running factory engine at operating temperature. It's either something major or else a combination of problems.

 

Even with the AC off the compressor will run if the selector is on Defrost, Defrost/Feet mix, or Feet regardless of what temperature you select. This is the same on almost every vehicle. It might be why the compressor is running when you think it shouldn't.

Is it coolant coming from your exhaust or just condensation? If you are losing coolant and don't have any obvious leaks it could be either your upper or lower intake manifold gaskets. Hopefully you can nail down your overheating problem.

 

I did get to the bottom of it. After replacing the thermostat, the radiator cap, the water pump, the fan clutch, and finally the radiator itself. Doing a system flush might have served to clog the radiator, but I imagine it was an eventuality. I'm running on just water right now with the intention of dumping out several times over the course of the next couple weeks in hopes of cleaning as much of the residual out as I can before I put in antifreeze for the winter. Thanks to everyone who chimed in with their $0.02.

 

Glad you found your problem and thanks for posting back up with your results.