kennyblatz

this year my truck is not producing heat as it used to. after a 1/2 hour of driving motor at temp it is just warm in the cab with the heat on full. at 32deg.F i can have the heat on full and it will just be warm in the cab i never feel i have to turn the heat down. any ideas at what i can look at befor i take it to a shop. thanks

badme

Mine was like that. The motor would not heat up enough so I changed the thermostat and the engine temp was back up to 190 degrees. I still did not have heat so I sent it to the radiator shop and had a back flush done. This thing will heat me out of the cab at 20 below now.

kennyblatz

had the full system flushed?

badme

Nope, he only did the heater. I changed the antifreeze about 2 weeks later for my 100K service.

Dinner

Could be a plugged Heater Core... My heat has been getting worse and worse throughout the winters. I replaced my Thermostat a week ago and haven't noticed much difference for in cab heat. Maybe sometime I will tackle my heater core.

Valv

Did you purge the system correctly ? If you have an air bubble in the system water will not circulate and will feel like it's not heating up.

kennyblatz

please explain further i had to drain some coolant this summer so this might be the reason. what do i need to purge?

oldblues

hi
try a simple back flush ,
remove heater hose from the tubes on engine and use a garden hose to flush heater core alternating between the two hoses several times till you get clear streem then reconnect the hoses and test drive.
bet you got heat now !

Tate

Do these systems really build much of a bubble in the core? I've been in and out of the heating systems in my trucks a couple times, and haven't had an issue with low heat out put. You hear some gurgling the first or second time (depending how long you run it), but after that, its all good. Thats been my experience.

Dr. Evil

Its currently -35F...not really an option.