I had my temperature spike to the max twice in the past month. The 1st I was pulling a 5,000 lb trailer and the second just normal crusing.

I pulled off the road both times, and the temp immediately went back to normal within seconds.

I thought possibly a hanging thermostat but my mechanic (who i swear by) says its time to replace the radiator.

My A/C has been crap the past few months and he says this could very well be the cause as well.

He says he would gladly charge me to merely flush the radiator but says he does not recommend it.

I am driving from Texas to Colorado in a few weeks and don't want any problems.

Any recommendations? My truck has 143,000 miles and I have never touched the radiator. Maybe its time?

 

A couple of things to throw out there. Not to cast any doubt on your mechanic but I would first check the fan clutch. Plus, the thermostat is real easy to check and replace (and cheaper too). Is your waterpump leaking any fluid? Even a small weeping of antifreeze from the weep hole on the pulley snout would indicate a failing waterpump. What was the reasoning for the radiator being the culprit?

 

Do you off-road your truck? Live in an area with a LOT of flying bugs?

The radiator may be packed with mud, leaves, or other debris that will considerably reduce the efficiency of your cooling system. You may have lost a lot of the airflow through the fins, and need blow it all out by simply blasting water through the cooling "stack" in a reverse direction than how the fan pulls the air through.

These cooling systems are among the few today that have a good amount of margin built into their capacity, and if your mechanic has been looking after the cooling system with the proper SCAs added, you shouldn't need a new radiator yet if it's a 99-03 SuperDuty. You didn't say what year, but the mileage isn't high at all.

I'd look for other causes than an impaired radiator.

Pop

 

I would look towards the clutch fan. When it gets hot You should here it, it is loud when it kicks in. I here Mine all the time when pulling my camper it the hot summer heat.

 

Exactly what Marv said. I didn't know how plugged up my tranny cooler, intercooler, and radiator was till I did the swap for a 6.0 intercooler. The transmission cooler was PACKED with dead bugs and gunk.

 

Ponyboychris:
I replaced the fan clutch about 4 months ago when I was having A/C problems. It was blowing warm air. Replacing the clutch fixed the problem, but over time the A/C has gotten worse. Tends to have issues at idle but get better when the truck is moving and rev'ing. Have not seen a single drop of antifreeze anywhere, everything looks good there. I am not sure why he pinpointed the radiator so quickly. That is why I am asking you guys.

Springerpop:
I do not offroad the truck, there may be some bug buildup but I wouldn’t say more than any other place. The truck is a ’03 w/only 143,000 miles. It’s a baby! Only thing I can think of (and I thought about this after posting) is I bought the truck used. It had been in a front end collision but everything seemed in order (bought w/83k miles). I don’t know if the previous owner off roaded it. It does have a 6” lift even though it is 2wd. I bought it cause we have flash floods and I need to drive through high water from time to time. Perhaps my mechanic is thinking there was some damage to the radiator during the wreck.

I appreciate all the responses, it definitely gives me some avenues to search through before purchasing a new radiator.

Thanks!

 

Here's a try for your AC issue (see post #3): https://www.ford-trucks.com/forums/5...ml#post4464164

 

I just put a new radiator in my '99 service truck. I replaced the factory one with 280,000 miles on it and only because the shroud rubbed a hole in it.
if you temp goes above normal your fan should sound like jet, if not your fan clutch is bad even if it is new.
my service truck was a hot shot truck for the first 200,000 miles and than a cowboy truck for the next 80,000 miles and it was not taken care of. when it needed water it got what ever was available.