Ok so heres the deal. All the sudden in the last 2 days, and 107 deg heat not helping truck is over heating. So driving normal temp is fine. Once i got into stop and go more stop then go she strated to heat up just under H line. Rolled down the window and can spell coolant. So I pulled over and sure enough she is spitting coolant out of overflow reservoir. So I turned the heat on high and she strated dropping temp down to halfway point. Let it run for a few min then shut it off and when into a resturant to get something to eat. Came out and went home. I went to the parts store grabbed a thermostat and new reservoir cap and coolant. I changed the cap and thermostat out and topped coolant off. Let it run at idle for about 30 min never heated back up. Temp out side had dropped to mid 90 by the time I did this. So today I went outside around noon and started the truck up and let it run for about 20min at idle and ac on high came back and she was at halfway. So I loaded family up and we left to go out. Drove for about 10 miles then came to so stop and go traffic and it rose just a little above half way but though ok may be due to the fact that the thermostat i put in was 195 deg. Well keep driving and then pulled into chick fil a and sat at idle for about 10 min in the 107 deg heat and and she started to heat up. The truck heated all the way back up to the H line and spitting out coolant again. The only time it really over heat is stop and go driving followed by a stop and idle and only in the day time when it is really hot outside. This evening I drove it around for about an hr and nothing stayed cool the whole time. Any suggestion would be appreciated.

 

I know this is going to sound weird, but you said it was just under the H on the gauge which means its hot. But it was not in the RED as to overheat. The overflow which I think is vented to allow for the excess heat escape/ pressure build up do to fluids getting hot. I think what happened is normal. You changed the thermostat with a 195 deg, was that a OEM thermostat and temp setting.

You can always buy a scangauge II, There are some threads on here about it. Its cheap and you can monitor all sorts of things (water Temp). Just do a search on here scangauge II. It has pictures and is an easy set up. It will give you exact reading of temp not the guessing game that the stock gauges do.

 

One thing, did the fan ever turn on when this is happening?

 

ok, it has never spilled over before. So this is why I am wondering what was going on different. When it hit H line I turned heater on to cool it down. Ya I dont like the gauges that have a C line and an H line I want one that tells me the exact deg. I dont know why they didnt put those types of gauges in there to begin with. As far as thermostat the one that was in there 185 deg and parts store only had 180 and 195.

As far as the fan being on I really dont recall if it was ingaged or not I was paying more attention to boiling over and steaming, watching temp gauge.

This seams to only happen in the hottest part of the day and when I have driven it for 10miles or so and come to a stop and sit at a long light or wait at the drive thru. If I just go out from and start it up and let it run it will run for 30 min no problem.

So far today what I am doing is flushing the system completely and then going to go get a different new thermostat to see what happens gonna call around to get another 185 or 180 and go from there. Thanks guys

 

I forgot about the fan. its an important part. Maybe a fuse or something for the fan if its not working. But I would check it before buying another thermostat or doing a flush.

 

Fan should have a thermal clutch. (non electric)... but you should here it engage.

Did you check your coolant blend? You may consider having it flushed. Refill with Zerex Gold.



What is the viscosity of your oil? Is it time for an oil change?

Other thought: How has your mileage been (mpg)? That is another reason to monitor your gas mileage as it can tell you what is going on in your engine. You could have an alternator, a/c compressor, power steering pump, etc that is dragging or putting extra load on the engine. Although with these as an issue the cooling system should still not run that high.

 

ok I check the blend friday and it was good. right where it needed to be. gas mpg has been consistant. the oil is 5-20w syn mobil changed by me has about 3k on the oil. still looks pretty good too. I just flushed and refilled with prestone antifreeze. Put a different brand of thermostat in it about 20min ago. autozone sold me the wrong one three times and keep insisting that the one they sold me was correct and there was now way because it didnt fit. goona take it out iin the heat to see how it does tomorrow. let it run for 20 min in the driveway.

 

This sounds like the fan clutch isn't locking up. When it gets this hot, the fan should make a LOT of noise when you accelerate. If you don't hear it whooshing, you need a fan clutch.

 

Many people forget about flushing the gunk out of the radiator and condenser after "cottonwood season". I flush mine every year, and it's amazing the amount of crud that comes out from between the fins of the radiator and condenser; all that sand, bugs, cottonwood seeds, etc, etc, etc. You can do it with a regular garden hose and sprayer; pull the fan shroud off and flush back to front through the radiator, then unbolt the radiator, tip it back, then flush the condenser. The condenser is a lot more difficult than the radiator as it's hard to reach a sprayer in between them. You may also find an accumulation of crud between the 2. Just doing this can have a dramatic effect on the cooling ability on hot days with low airflow like in traffic or idling.

The thermostat obviously wasn't the issue, you know coolant is getting to the radiator. The radiator cores could be partially clogged, but that isn't very common. The fact that it cooled off with the heater on (essentially your heater core becomes your radiator) indicates you definitely have a radiator or fan issue.

 

Ok so I did put new thermostat lastnight after a total flush. I did also spray down the radiator to get the bugs and crud out. Took it for a drive today and the pulled over to the side of the road and sat a idle in Drive to simulate a wait at a light for about 15 min and it never got pass half way on the temp gauge. The outside temp was ten deg cooler today then it was over the weekend though. So for now I am gonna call it good and keep an eye on it. I will be pulling a trailer later this week so I will beable to see how it does then. Thanks everyone.

 

Thanks for updating your thread. It sure makes it easier for other readers to find issues and repair them.

 

ok I am getting really fusterated with this truck. Since my last post I have moved from fort gordon to fort rucker and have made three trips about 350 miles each during that time never had a problem of hit heating up. However once or twice last month for no reason it would start to run hot, on the the gauge so I would pull over pop hood but truck never showed any sign of being hot didnt boil or spill over. Then last week to a drive down to panama city which is about 90miles from where I am and about 60 miles into the drive it started acting like it was heating up. Gauge go up, turn on heater gauge goes down did this game the last 30 miles til I got there. Parked truck at hotel then used it the rest of the weekend without any problems. Then drove it today to go to town about 30 mile trip and ten miles into the trip it heated up on me. Came to a stop like and I wasnt looking at gauge was looking at traffic then check gauge light came on and truck went into overheat protection mood which made it hard to drive pulled over right away popped the hood and coolant level was fine and was not boiling over or anything. So am I really getting hot are is it possible that the temp sending unit is telling the truck I am hot. Also I was going to replace the sending unit, I bought a new one and looked at the book on it and the spot that the book tell me that it should be in only has a plug there is there another spot where ford has put these on this truck. its an 04' v10. thanks for any information.

 

You still haven't said if the fan came on for any of the problems....

 

fan seems to be working fine

 

It sounds like you have a completely different issue than before. The first problem was boil over after stop and go traffic. The new problem is the gauge showing hot when driving, with no actual boil over. It sounds like all the previous boil overs ruined your temp sending unit. I can't help with locating your sending unit on the engine, but I think you are on the right track.

By the way, are you using a factory service manual? If not, that may be why the diagram is wrong.