For those that have a Tahoe around the 2013 year model, when you are using HEAT and floor only, does your Tahoe still blow heat out of the defrost vents also or just the floor only?

Mine will not blow heat out of just the floor vents only. Every time I have it on floor only, heat comes out of the defrost vents. Basically, the only way to get it to NOT blow out of the defrost vents is to put it on the passenger vents that blow directly into the passenger compartment...i.e. like when you are using the A/C.

I just recently got this Tahoe and trying to figure out if this is normal or if I need to take it to the shop to get checked. I have pulled out the actuator from under the glover box and even manually turned the actuator and that does not adjust air flow to the vents, it must just be HEAT vs COLD.

 

Are you sure you have it set to full defrost? On my '14 Equinox and my '06 Dodge Ram 1500, they both have settings where it blows air out the defrost AND the floor vents. It's easy to mistake the full defrost from the defrost/floor setting.

 

Every vehicle blows some air out of the defrost vents when set to floor heat. Normal as to keep windshield from fogging as if it's cold enough to need heat windows will fog.
My entire GM fleet does it and all the previous ones too.
At sub zero temps you get a nice fog halo around the windshield when on floor only.