04 Psd Overheated

[elgatoprerunner]

I was pulling my 31' toyhauler up the Cajon Pass last week and I noticed a CHECK GUAGES light come on. My engine temp was just under the red. These were the conditions. 04 Excursion 31' toyhauler loaded with 150 gal of water, 105 deg outside, running 65 up a fairly steep grade, with the AC blasting. Should this have happened? I don't think I was pushing the vehicle very hard, it was pulling the grade very well. I pulled off to the side and the temp came down almost emediatly. I popped the hood and noticed the coolant fill was below the cold fill mark. I just checked it today and it was at normal. I don't get it. I thought when the engine gets hot fluid is forced out of the radiator and catches in the resivior. I would appreciate any advice. Even if it is to slow down.

[mschn99]

Originally Posted by elgatoprerunner

I was pulling my 31' toyhauler up the Cajon Pass last week and I noticed a CHECK GUAGES light come on. My engine temp was just under the red. These were the conditions. 04 Excursion 31' toyhauler loaded with 150 gal of water, 105 deg outside, running 65 up a fairly steep grade, with the AC blasting. Should this have happened? I don't think I was pushing the vehicle very hard, it was pulling the grade very well. I pulled off to the side and the temp came down almost emediatly. I popped the hood and noticed the coolant fill was below the cold fill mark. I just checked it today and it was at normal. I don't get it. I thought when the engine gets hot fluid is forced out of the radiator and catches in the resivior. I would appreciate any advice. Even if it is to slow down.

Thatts a pretty good sized trailer, with a very hot temp outside. Im guessing you dont have a problem, the cooling system of the motor just exceded its capacity to cool. Having the AC on makes all that worse. Your best bet is to do just as you said, dropp it into manual 2, and slow down. You souldnt run your AC on a steep grade when towing when the ambiant temp is that high either. I know its hot, but if i was you, i would get it good and cold in the cab and then shut the AC off when you hit the grade......those are some pretty extremem conditions....and since you are not having a consistant problem, i think its probably just related to the heat, steepness of grade, and how hard the motor was working to maintain that kind of speed....

[Harley Truck]

I dont want to hijack your thread, but i too was having the same problem with my 04 PSD. We've pulled small trailors with the truck before, but this was our first time hauling our big 32' fifth wheel. It was kind of hot out, probably low 90's, so we had the AC on. Anytime we hit an uphill grade temps would rise. after the grade they would go back to normal. We were only cruising at an easy 60mph. We took it to Ford afterwards, they drained a little coolant (?) and messed with the timing on the radiator fan. We havent hauled with it since, i just wanted to see if this sort of thing was normal.

[Harley Truck]

I also wanted to note to anyone else that may have this happen - blast the un-circulated heat to help cool the engine if you dont have time to stop on the side of the road. We did that and our temps stayed within reason for the rest of the trip home.

[mschn99]

the problem you run into is the cooling fan is only capable of cooling the radiator so much. the engine is running at about 190 with everything operating at max efficinecy......

You hit an uphill grade, with hot temps, with the AC on, and pulling a HEAVY load and trying to get to where your going faster.....you have reached the capacity for the water pump to move enough water throughout all the passages and keep the motor cool. if you slow down to about 45 on those grades, downshift into manual two to keep the RPM's, and thus the water pump speed up.......the motor doesnt have to work near as hard to maintain 45 so it doesnt build enough heat to overheat.

What you guys are experiencing is towards the exteme end of what any motor is capable of. A gasser probably would have overheated even sooner since they tend to run a bit hotter....and it wouldnt have pulled the load that fast up the hill....

Now another point, if the temps just go up, but dont reach the upper part of the normal range, then dont worry. That "normal" range on that gauge is only about 60 degrees. It doenst take much to make the gauge move. When the gauge goes from halfway up to three quarters, it looks like a HUGE jump, but actually it was only 15-20 degrees, which is nothing to worry about......When the whole range says Normal, it is just that.....and an increase on a hill is to be expected......at least when the temps are hot

[Harley Truck]

Thats what i was assuming, just wanted to make sure it wasnt something to worry about. Ford didnt seem to concerned after looking at it, just wanted to see what you guys thought.

You dont suppose installing a lower temp thermostat would make this not happen? Based on your response im guessing not.

Thanks for the input Marc!

[mschn99]

Originally Posted by Harley Truck

Thats what i was assuming, just wanted to make sure it wasnt something to worry about. Ford didnt seem to concerned after looking at it, just wanted to see what you guys thought.

You dont suppose installing a lower temp thermostat would make this not happen? Based on your response im guessing not.

Thanks for the input Marc!

a lower temp T stat could make it take longer to happen, but the thing to remember is after 190, that T stat is wide open all the time anyway......and your temps still climed.....

Just turning your AC off during the uphill might allow you to still maintain the speed and not have the big temp increase, but if it was me, i would just slow down and leave the AC on to keep me cool....lol