EvilWS602

We did a very minor tune when we turned the fans on over two and half years ago. We really just adjusted a few things to try and help the mpg in that pig. I'll get my him and have him check the timing and the tune just to see. I was going to have him re-tuned it for some more ass after a few performance mods to get a little more grunt out of that turd, but I've grown tired of spending time and on money on that truck. But to answer the question. Truck ran fine for 2 - 3 years after being tuned.

I guess I'll have my tuner check the timing bc we did some very miner tuning when we activated the factory e-fans.

This is a gas 6.0L. Only thing that came in the 1500HD's. I have not noticed the coolant boiling out yet but it only spikes on inclined and starts to cool back down on the decline and coasting so it comes out of the reduced power mode. I bypassed the heater hose and connected the two together at the beginning of the summer. Now that the ambient temps are reaching and exceeding 100 it has been more apparent. I believe it won't be as much of an issue once temps outside finally drop. It it makes it that long before burning up lol. And the new radiator fins looked good from the inspection before I installed and did not bend any during installation. Tans Temps are good while towing....

Only other thing I thought of is that I have my heater hose bypassed at the fire wall. It started leaking at the beginning of the summer into my vents so I just bypassed it. We ruled that out from being part of the problem bc it is still before the water gets to the radiator to be cooled. Still stuck....

Only plastic piece that isn't installed is the very top piece that goes to the grill and upper radiator support. It hasn't been installed for about three years though when I put a new grill on the truck. I did pull it out the scrap pile the other day so I can reinstall it just incase. The fans are running in the proper direction and have been installed and operating fine for over two years. Condenser is not clogged and no bug screen. Trans temp and all other gauges read fine while towing. The temp gauge has pegged out while climbing inclines and went into reduced power. Does that mean the ECM is also reading the same as the gauge? I will borrow my buddies scanner next time I tow and monitor it all through that to verify what my dash is reading. I believe the problem is steadily getting worse though bc it is even doing it with light load now when it use to only be heavy loads. Also just the past couple of days the temp outside has been in the 100's and not towing anything with typical everyday driving the temp gauge has gotten to 225 degrees or so on my way home in the evenings but does fine in the mornings.

I might recall the truck getting slightly hotter towing before I swapped the radiator for an OE Acdelco HD. Only reason I changed it is because a tank cracked and was leaking. I changed both upper and lower hoses when I changed the radiator. The overheating was becoming more of an issue bci was towing more often so I believe I had a 160 thermostat in it. My buddies and I could only come up with the conclusion that it was allowing to much water to flow not giving it time to cool off in the radiator. So I swapped it for a 186 and still same issue. E-fans or fan clutch I belive is moot in this situation. Going 70mph down the interstate I should be able to pull the fans out of the truck and it not over heat, there's plenty of air flowing through the front of the truck. But they are OEM GM fans out of the newer trucks. A couple of years ago I put in a autoparts shop water pump from O'Reilly's. But it obviously pushing plenty of water bc my heater house connection has broke a few times and it pushes out all the coolant in the matter of seconds. Also flushin out the coolant system lol. Still stuck at square one....

It's a brand new Acdelco radiator a month old. Had to replace it be a tank tracked.

I drive an 03 1500HD 4x4 with 4.10 gears that has 230K miles on it. Truck does great when not towing even if I keep the pedal to the floor, but as soon as I hook to a trailer even with a light load, like 1,000 pounds, it starts to run hot. It runs 220 - 230 down the interstate at 60 - 70 mph turning 2k rpm and about pegs the gauge when I climb and incline. I replaced the water pump about 60 - 80 thousand miles ago, the radiator, thermostat, and all the coolant just less than a month ago. The radiator is an Acdelco GM replacement. I put a 186 degree thermostat in it I believe. a couple years ago I removed the factory clutch fan and installed the newer factory dual electric fans in its place. but those do not come into play while the truck is moving down the road. They do their part by cooling the truck down while I am stopped. I know it is a very hot summer here in Louisiana with temperatures reaching 100 degrees but why does is this only an issue when I hookup to a trailer? Any help is greatly appreciated being that I've tried everything I can think of am I am still left scratching my head. Clint

I know this is an old thread but I am have the same issue. I drive an 03 1500HD 4x4 with 4.10 gears that has 230K miles on it. Truck does great when not towing even if I keep the pedal to the floor, but as soon as I hook a trailer even with a light load, like 1,000 pounds, it starts to run hot. It runs 220 - 230 down the interstate at 60 - 70 mph turning 2k rpm and about pegs the gauge when I climb and incline. I replace the water pump about 60 - 80 thousand miles ago, the radiator, thermostat, and all the coolant just less than a month ago. The radiator is an Acdelco GM replacement. I put a 186 degree thermostat in it I believe. I know it is a very hot summer here in Louisiana with temperatures reaching 100 degrees but why does is this only an issue when I hookup to a trailer? Any help is greatly appreciated being that I've tried everything I can think of am I am still left scratching my head. Clint