Weak defroster vent airflow

[DMAXMO]

I had my '02 D/A CC to the dealer yesterday for a couple of warranty repairs. I had asked them to correct a low airflow problem from the drivers side defroster vent. Air flow is strong on one side of the vent but is noticeably lower on the side towards drivers door. Makes defogging the windshield difficult,fan speed must be on high to defog at all. Dealer called the condition normal. Anyone else had this problem? Any insight will be appreciated.

[FirstDiesel]

I think this has been discussed before. Something to do with the routing of the air under the dash. Try doing a few searches on the forums and I think you'll find some answers.

Start here:

http://forum.62-65-dieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=7&t=003802&p=

[ 01-01-2003: Message edited by: FirstDiesel ]</p>

[DMAXMO]

FirstDiesel
Thanks for the link. My own searches had not found that particular thread. Doesn't sound like a definitive fix is out there. Is this a common condition on CC D/A's??

[FirstDiesel]

I think it's standard do to the routing of the ducts.

[wangotango]

Hey Bigdog:

I have just recently discovered the same thing on my 2001. The side window will only clear if the fan is maxed.

Am looking into it.
Will take a in-depth look this weekend.

It's too bad that normal is that it doesn't work.

w/t

[wangotango]

Upon further review:::

Good link from 1stdiesel.

It's an objectively depicted explanation of the co-efficiency of heat transferal and the relationship of matter in a selected volume of airspace occupied by 1-4 mammals on any given late-evening in the cabin of a diesel powered vehicle.

No further questions.

w/t

[GMC-2002-Dmax]

I have the same problem with my 2002 Crew Cab.
What I have found is that most of the air that is supposed to go thru the defroster vent is somehow blowing out of the rear seat vents in the console. I closed them off and it works much better.

I will be having the dealer look at the reason why the defroster is blowing the air from the vents in the console and not the dash vents.

I assume the vent is a vent and the floor is the floor when I set the controls to that setting.

Am I asking too much for 40 grand??????

Check yours out and see if it is the same.

GMC