My buddy had a pos car that blew up(at his house lol) and he wantedme to take it to the scrap yard for money, along with other things that where worth money. When I weighed in i was at 18K total. On the way out i was at about 14K. I didnt take the freeway on the way there since some of the stuff wasnt strapped down too well, and i needed to go slow. I was very impressed on the way it handled the load on the way there. I had to downshift one time to get my egts down. On the way back i was going down the freeway at about 78mph, and i was doing it for about 10 minutes and i look down on my "dummy" coolant temp gauge was not in the red, but it was about 3/4 of the way to the top. I drop speed and it goes down. I thought these stupid gauges only had 3 spots, cold, normal, and your screwed, and was i just over loading the motor with that amount of wieght coupled with my tire size on stock gearing, and the speed i was going? I can't even start beginning where to look into this since it doesnt happen normal driving. I was going 90 today and that was for about 20 minutes and it never moved.

 

The temp guage is a real guage, unlike the oil pressure. Did you ever notice your fan clutch engage ( new "roaring" sound under the hood)?

 

I didnt hear it. I think i hear it when my ac is on though. Anyway to check the clutch to be sure its turning on at the right time.

 

It's a liquid clutch, if there's any evidence of it having leaked it is probably bad or on it's way there. What kind of trailer were you pulling that weighed 6000# empty, if myt math is correct?

 

It was a 10 ton, dual axle, dually(2 wheel per side per axle). I got some pictures of it, but i just got the laptop fixed. Ill post them tommorrow maybe of the truck and trailer, and some of the car getting on the trailer(very funny seeing a car on its side). I also got the wieght sheet.

 

You sure about that?? Mine never moves from the same spot (once it warms up) no matter what time of year it is. That may be because the cooling system is so good, or it's because the gauge is a POS. I'm pretty sure my Ranger's temp gauge was a glorified idiot light, too. I never verified it, but because of the way it behaves I assumed it was like the others.

Joe

 

The stock temp guage in my 1990 mustang 5.0 notch is a real guage. I don't know about these trucks though.

 

It's measuring actual coolant temp, and your behavior is normal, and it just means that your thermostat is functioning as it should. When I tow in the heat mine doesn't move very much, but the fan clutch engages full on and the extra flow through the radiator keeps the coolant temp about the same as running empty. When I pull in to a rest stop and use my IR thermometer, I typically see 190-200 F on the top hose, and about 160 F on the bottom hose, which tells me that both the thermostat and radiator are working normally.

 

Ernest since you pull some weight, ill ask you, does mine sound correct, or could it be caused by something wrong.

 

sounds like you found your problem with a pin hole in the lower hose...

 

It hasnt been leaking before though. It got a hole in it from the radiator shround. It just came out of no where yesterday. I wonder if this well fix my problems.

 

Well, I'll have you know that currently I only weigh about 165 lb soaking wet, the same as I weighed 50 years ago in high school. In between then and now was a different story, and the composition of my 165 lbs now is a little different, but I never did have all that much weight to pull!


The gauge on my early 99 doesn't have color coding, but I know it's reading actual coolant temp. It starts at 0, and slowly and continuously increases to about 1/3, and then the thermostat opens and the flow through the radiator stabilizes the temp at that reading. Under the worst case towing conditions, I've never seen a reading quite up to the 1/2 mark. When I pull into a rest area and pop the hood I get the #'s I gave above. An IR thermometer is cheap, and a nice way to measure temps for trouble shooting, and just to see how hot everything is getting. If you get one and check the temps on the hoses you should see a 30 to 40 degree delta, indicating that the thermostat is open, the water pump is providing good flow, and the radiator isn't clogged up.

I don't think a small leak will increase your coolant temp as long as you keep the level topped up. A larger leak can reduce the pressure enough to decrease the boiling temp, but you'd probably see steam or a stream of coolant coming out from one that large.

If I compare your 78 mph w/trailer to your 90 mph empty, I conclude that you drive way too fast whether you're towing or empty! I also conclude that at 90 empty your engine is producing as much or more HP than at 78 towing your empty trailer. Running empty, it takes 50% more HP to go 90 than to go 78, but it probably takes about 50% more HP to tow at 78 than empty at 78. Since the waste heat absorbed by the coolant depends on the HP, you should see about the same load on the cooling system in the two cases.

So why did you have a higher reading in one case than in the other? I've been told that if you tailgate too closely behind a semi you'll block enough RAM air to the radiator to increase temps, and also stories about plastic bags etc getting temporally stuck on the grill or the AC condenser and increasing temps. You might want to check my post # 59 here, where I yak on about my view of waste heat vs HP, RPM, gear ratios, etc...https://www.ford-trucks.com/forums/623589-need-to-talk-gear-ratios-and-other-stuff-4.html .

 

Ernest you were right about blockage it turned out to be a mud packed radiator. Mine doesnt have colors either i was just refeering to the gauge being all the why to the H as the red zone. Thanks for your help everyone!