I can tell you are frustrated, all in all it sounded like a good trip. I will also agree with glen on the 180 t stat.

I used an OE ford unit and pulling maybe 6-7k over Colorado passes the truck was running way too hot. I was able to get it over the L on a 60 degree day and not on the floor the entire time. The truck always ran unloaded around the N or O in the summer. After I did an OE pump and t stat it was running up in the R to M area when cruising unloaded, and that's when the temp issue arose. The old t stat was a 192 unit, go figure.. the new motor craft is 195 I believe, someone correct me. . The point is when I put the 180 and took out the OE stat I was back to cruisn by the N, and during the winter with heat on it's even below N. heat is just as hot as ever too.

lately I was pulling 17k over Eisenhower with it on the floor the entire way (9 miles of thin air :-)) I was able to get it back to the L but no more. Cooled back to N within 2 miles on the back side, but again I thought that was a bit hot on a 50 degree day, but she was working.

I don't know what it is, some trucks react different. I have seen a lot of 7.3 fleet trucks I regularly service and have towed 8-10k with react the same with a 195 in, and some that have the same issues as mine. The fact of the matter is it should not have the symptoms like mine with a standard 195 OE stat.

I'd also suggest running an OE pump from Riffraff. It's worth the extra 80$ and I have only seen one fail prematurely, I have seen dozens of your Mexico fabbed units from autozone (insert generic store) go bad within 3k, I have seen dozens not as well. I however will not install one or guarantee labor on one unless it's an OE unit.

If I remember you already have a mishimoto radiator in there, they cool a lot better than the OE units IMO.

You got a diamond in the ruff but you will be more than happy with it when all is ironed out. I am blown away a truck of nearly 20 years performs as well as it does when beating the crap out of it on a daily basis. I used to treat mine like a street queen but those days are long gone:-)

 

I thought it was a 192° but maybe it was a 195°? Anyway, I agree with the OE WP, I got mine from Dieselsite.

 

who did the pump?
I have seen and heard of pumps being installed with the protective plastic or cardboard ring still on the impeller. rendering it almost useless.
as for a fan clutch unless you are towing heavy you don't even need a fan at highway speeds, to over heat at 39 degrees you have other issues.
but if you cracked a radiator and lost the coolant it would get real hot real quick towing.

 

I'm not sure why the quick jump to the fan clutch is so common on the internet. Besides slow moving traffic in the middle of vegas the flan does not do all too much for these motors when moving over 10 mph.

 

I did all the work on this truck. for the first time I have taken it to a shop in town to do things I can easily do and a few I'm stumped on. I just don't have the time or the warmth and light after work to do it... the pump was good. I took it over the mountains not long before this with no issue but I was not hauling *** up hill. but I was going up hill. This whole thing has me stumped. The shop is doing a block test too. Make sure I don't have a blown head gasket.

 

Well some good news. Block was tested and not leaking. new Rad is in. getting new shift bushings. ABS still not working. Shop wants to replace Speed sensor but I put 2 new ones in already.

 

I thought you put a brand new mishimoto radiator in it? Block tested? Hydrocarbon tested the coolant?

 

new Mishimoto in it today. block was tested but I don't know about hydrocarbon test? the shop said it was going to get retested when it is all complete.

 

Maybe they do an oil diagnostic, seeing if you got coolant mixed in.