After 6 inches of rain. It started to snow and my heater isn't working on my truck. It was blowing warm until I switched it to defrost and then no heat at all. The temp is showing 200 so the truck is at operating temp. Any ideas on where to look to solve this problem. I have an 07 5.9.

 

I would start by checking my coolant level.

After that, the only thing that would really affect that is your blend door is inop.

 

Coal train, It was the coolant level. Replaced the hoses and checked the water pump weep hole. It is leaking somewhere on the bottom. It seems that is coming from the area of the corner of the oil pan on the passanger side. I've tried to find out exactly where but I can seem to see where it is coming fom.

 

I bet it's not leaking at the bottom.

I bet it's leaking right at the top passenger side of the radiator.

Look on your airbox, I bet it has coolant and/or coolant residue on it.

The hose to the resevoir is there and the hose is just pushed onto the fitting and they leak.....they all leak.

Lemme see if I have a picture of the area I'm talking about.

 

Here ya go. These are 2 areas to check.

The first is the top of the radiator, the second is behind the exhaust manifold.

Both are a common problem, but are easily fixed with a few hose clamps....

 

Any luck?

 

Coal Train, I lost the light of day and my wife brought me into work today. I will check it as soon as I get home. I know the hose by the cap is on. I didn't even think to look at the other one. Thanks. I'll let you know this evening how it turns out.

 

Oh, I know the hose will be on, but it leaks without a clamp on it.

It may be pushed all the way on, but that hose always leaks. Almost every 3rd gen truck does right there.

The other one, under the exhaust manifold usually does it when there are wide temperature changes. If it's cold one day, warm the next, cold, warm, etc...... that is when that one will show it's face. It usually does it in the spring and fall.

 

The weather this past weekend had a lot of temp swings. Friday in the 70's with 6 inches of rain and then cold saturday and sunday with 4 inches of snow. I'll clamp both hoses tonight. Thanks again for your help!!!

 

No problem.

Anytime.