Just got back from a camping trip today and had a little overheating trouble.

Prior to the trip, had the dealer do a oil change and tranny service. For some reason, my truck was running extremely hot on the trip after the dealer work. I checked the fluids and they were fine.

Now granted I was pulling my pop-up trailer, but I have done it several times before and never had a problem and c'mon, the trailer doesn't weigh hardly anything. The only thing I did notice was a finemist from around the bottom of the plastic filler neckwhen I pulled over to see what was going on. I checked to see if the coolant was low but it is within range. I'm thinking the mechanic leaned on the rad cap when he was servicing my engine and possibly caused this fill-neck problem, But that shouldn't cause the excessive heat. Oh, and I did buy a new rad cap while I was in town to see if that would fix the problem but no luck...

I'm thinking I might have a partially open thermostat. Is it housed in the bottom rad hose mount at the block? It's the most obvious looking place that I can see. Is there anything out of the ordinary changing this style?

I had to keep her around 50mph all the way back to keep it out of the red and when I sat at a light, it would cool down a bit which I thought was not normal for a vehicle that was over heating. I've always see them cool down when you were moving and heat up when you were sitting.
If anybody has any ideas, I'd appreciate the help.

Thanks

 

I just finished swapping a thermostat on an 04' 4.7 for my friend. His was stuck closed and was doing the same thing,it would be fine for an hour or so and slowly creep up to hot. I put his stat in a pot of water on the stove and it would open,but not fully. Another thing I did was a full rad flush, he had never changed his antifreeze so I figured since I was in there I would drain it all. I found quite a bit of sand in the rad. So I flushed it. Sometimes casting sand will not be fully cleaned out of the block before assembly. Drain the antifreeze in a clean bucket and let it settle for a few minutes,put your hand in and check for fine sand in the bottom of the bucket. If you feel grit, do a rad flush as this sand can clog the radiator and wear on the moving surfaces of the water pump! Hope this helps!!

 

Sounds like what I'm dealing with. A couple of questions if ya don't mind:

1.So the thermostat is in the bottom rad hose connection to the block?

2.By radiator flush do you mean the Prestone style flush additive that you add to the cooling system, run for a while, dump, repeat...etc?

This newer vehicle can be little intimdating for me to work on. I can work on any of my older cars without a problem but there is none of the new-fangled equipment or systems to deal with...

 

Sounds like youve got it down pat! Yes, the Thermostat bolts between the lower rad hose and the block. I used a Prestone flush kit to clean the rad, I got the one that connects in line to the heater hose and hooks to a regular household water hose. Flush it with the thermostat out so water will flow freely throughout the system.

 

Thanks for the info...

 

Might be a good time to try a 180* thermostat since you are gonna get one anyway. A good many of us have switched to one with very good results. Will keep your engine cooler and with you being in a warm climate anyway, cold weather will never be an issue.
And I agree, with it being an '02 you are do for a 'stat and a flush, will probably fix you right up!