Hey everyone and merry Christmas!!
looking for advice and where to go about getting more heat out of the truck. It's the coldest day of year so far since February at -35. The truck fires up no problem when plugged in. I have a winter front on the grill and a corrugated plastic sheet infront of the rad to keep the cold air off it. So I get decent heat not amazing , when engine gets to operating temp. Enough to defrost the windows but not nice and toasty inside. Soon as I hit the highway today the warm air was barely there ! It's starting getting so cold inside i had to turn around and go home. It doesn't make sense cause my trans temp was good engine temp was good ( even though the temp actually starting getting a bit hotter since everything was covered up) and it was still blowing Luke warm air! I don't get why it gets warm when sitting there but soon as your moving on the road gets colder...
coolant level is right. Thermostat was done last year. I back flushed the heater core last year aswell but could it be on its way out ? I wanna get this figured out asap as I love driving this thing around in the snow ,( it's not my daily.) Any tips where to start would be great
happy new year yall

 

It's a '96?

 

Yes sir. 1500 5.9 4x4

 

Does it have enough antifreeze in it? At -35 it could be starting to freeze up blocking flow to the heater core.

 

Yes I believe so. Right up to the neck on the rad cap . Stupid question but the overflow tank beside the rad Is only for overflow right ? Like it's not supposed to always be full?

 

If the heater core is original, it's way over due for replacement.

 

Yeah, that tank is just overflow. Should be markings on it for "Full Hot", or some such.

Might still have some air trapped in the heater core as well, so, not as efficient as it could be. These trucks are notorious for that kind of behavior.

 

Ya I just find it weird that there's some heat when parked / idling and then when your on the highway it's starting getting cold / Luke warm air. I mean I get it there freezing air hitting it the faster you go but it shouldn't be that bad. Could a bad thermostat maybe ? Or is it looking like heater core for sure?

 

What does your temp gauge do on the highway? Does the engine run colder than normal? Heater core gets its hot water right off the intake, so, radiator shouldn't matter, so long as the thermostat keeps the engine at a fairly stable temp, close to what it is rated for, your heat should be consistent as well...... If it were a low coolant thing, I would expect heat to be BETTER at highway speeds......

 

Temp gauge is a funny story. My motor was rebuilt and has a 2001 in it. Truck is a 96. So the intake manifold only had 1 hole for the plug of the two wire set up. I had to drill a hole in the location where the old intakes has the sending unit wire and installed one. before my temp gauge didnt work at all. Now at operating temp it actually reads a little over half when it's up to temp. Yesterday it was actually running a smidge hotter actually which makes sense cause I'm suffocating that rad completely if I removed the cardboard it prob get right back to temp. This now makes sense why it could be the heater core ? Is there a way for me to test the heater core for failure ? Or could my thermostat be toast already? I need heat on my road trips! Lol