what is the mix of your coolant? is it 50/50, 70/30 or some variation of? What would you guess?

 

It was pretty close to 50/50 then i drained some and put in a little over a half a gallon of just antifreeze.

 

you should be okay as long as you don't break 70:30 of af:h2o...

where are you getting your temp reading from? the dash? have you by chance pulled the sensor/sender out for a new one?

I'd be curious to see if a block on the radiator caused your temperature to rise- just for grins, why don't you do that? You can warm the truck up by driving a few miles, and then park it with something obstructing the air flow to the rad..

there is no way your temperature won't rise after about 3~4 minutes.. If it doesn't display such, there is something wrong with your sensors.. if it does display a pretty good jump in temperature you've got something else going on.. I'd like to know what it is, because I'd recreate that in a heartbeat for folks who have issues running warm... But, if that's the case (which I doubt), you may need to go to a hotter stat until you figure it out...

edited to ask:

what caused your concern? are you getting a 1281? Are you running a programmer of some sort or otherwise altered the PCM?

 

I'm getting my temp reading from the dash gauge. I will try blocking the radiator from getting air tomorrow. My concern with it all was my gas mileage went way down. I drove 65 miles and it almost took a 1/2 tank of gas. I have no codes as of right now and I'm not using a programmer. Ill let you know tomorrow what my results are.

 

If you can get your hands on one, try taking some temps with an infrared thermometer and see what you come up with. It's more accurate.

I had the same problem as you. The only way I can get my truck over the 170 range is to block off either some or all of the radiator, depending on how cold it is outside. Evidently, the rad is pretty efficient.

I have the 190 thermostat installed as well.

 

Also, its not unheard of for clutch fans to give up the ghost. Is there any mud and such in the temp element on that thing? Is it never disengaging? That by itself could account for the 15~20* difference you're seeing.

 

Ok so i took a drive into town today and my temp seemed to get up to around 180. Came home and left it running and cut a piece of cardboard out and stuck it in front of the radiator and my temp jumped up to around 190-195. One question i got is shouldnt my clutch fan kick off once the engine gets up to temp? Even when it was at 195 it still was running. I had a new radiator and clutch fan put in about 3 years ago also. And should i just leave that cardboard in place till i find out if my fan is stuck on? Thanks for all the info again guys.

 

If will still freewheel on there. I wouldn't suggest trying to stop it with your fingers either. (don't ask.)

 

ouch!

 

help me visualize this:

you ran the truck up to 180*, then left it running w/ cardboard blocking the rad, and it only went to 190-195*?

your clutch fan should NOT be engaged up to operating temp.. It will still turn, but not near as hard as it will when the spring thing expands enough to engage it, which happens when temperature rises- and in effort to draw air through the rad to cool it off.. when the springy thing cools and contracts, it engages the clutch which disengages the fan from spinning under power and releases it to inertia....

was your clutch fan engaged and pulling air (basically trying to suck that cardboard through the grill), or was it just spinning as inertia carried it? If it was trying to suck the cardboard through the grill- (which is what it should have been trying to do) all is well, if it wasn't, you've got something weird going on..

If that truck was at operating temperature, and cardboard was blocking the rad for 3~4 minutes, I would be stupified if it never broke 200~210*.. If that cardboard was being held firmly to the grill, that means your 'clutch fan temperature springy thing' is working, and it was trying to do its job.. It also means the 'spring temperature thingy' in the fan is NOT agreeing with the temperature your dash says the engine is running.. I'd trust that clutch fan coupled with the fact you totally blocked the air flow from cooling the coolant in the rad..

I'm thinking you have a bad temp sensor/sender..