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pretty bad
Typical Repair Cost:
Average Mileage:
113,163 miles
Total Complaints:
10 complaints

Most Common Solutions:

  1. not sure (8 reports)
  2. how about gmc suggesting something (2 reports)
2004 GMC Sierra 1500 AC / heater problems

AC / heater problem

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2004 GMC Sierra 1500 Owner Comments

problem #10

Oct 092013

Sierra 1500 300

  • Automatic transmission
  • 85,128 miles


For some unkown reason my heater in my truck will only work on high (NUMBER 5) position and no other position. What the F-----. The money I paid for this truck and they put a cheap peace of S--- for a heater in the truck. Wow, I remember the good old days when the heater just worked for the life of the truck. Where has the quality control gone? Just one more reason to move onto to a Ford.

- , Peterborough, Ontario, canada

problem #9

Sep 092013

Sierra 1500 SLE 4,8

  • Automatic transmission
  • 240,000 miles

The AC and heater would work at the same time in the hot summer months, then during this time it would rain and turn the windshield washers on, then they would not turn off, they would stay on. I have then the air bag sensor is not correct, don't know if the airbags are on or not.

- , Conway, SC, USA

problem #8

Oct 042012

Sierra 1500 SLE 5.3L V8

  • Automatic transmission
  • 138,000 miles

It's funny cause I thought it was a problem that only I had...and was saving to take my car in. air comes out of the drivers side vent, with the air conditioner on or off...while the passenger side is nice and cold. How is it that no one could give us an answer to this problem....many issues have been reported.

GMC should stand behind there product and consider a recall. The shops act like they have never heard of the problem...All they say is, bring it in we'll test it and charge 'n arm and a leg..then say they couldn't find anything....REEPERS!

- , Salinas, CA, USA

problem #7

Apr 012012

Sierra 1500 Limited 3.2L V6

  • Automatic transmission
  • 66,000 miles


Drivers side will blow hot air while passenger side is cold. While your driving it will get more frequent when you slow for a stop. You have to turn off the ignition to get it to work correctly again. I have had to replace ignition switches because of the frequency and repair costs from the dealership are saying $2000 plus they have to keep the vehicle for at least two weeks. GM should do something about this it is a common issue.

- , Midland, TX, USA

problem #6

Jun 152012

Sierra 1500 4.3L

  • Manual transmission
  • 164,000 miles

Have never had a problem with the a/c, has always blown ice cold until about a month ago while driving starting blowing extremely hot air. Went home checked fuses to see if any were blown. In which none of them were. The next morning got in and it was working fine. About a week ago it did the same thing and I pulled out the fuses and put them back in and it started working again. What the !!!!!! Spoke with a friend that has the same truck he said his and his dads truck did the same thing. This definitely needs to be looked into because it seems to be a very common problem.

- , Middleburg, FL, USA

problem #5

Apr 182010

Sierra 1500 Crew Cab 4.3L V6

  • Automatic transmission
  • 94,500 miles

When I turn on the AC, it works but sometimes the pilot's side turns into a heater without any reason; the co-pilot's side is fine. I think that a relay needs to be replaced but I haven't yet.

- , Tucson, AZ, USA

problem #4

Jan 132011

Sierra 1500 V6

  • Automatic transmission
  • 60,000 miles


the a/c in my 2004 gmc sierra started to not work on the # 5 setting the the # 4 went out and now none of them work and i asked a couple of my neighbors and they have the same problem. we looked at the wiring harness under the dash in the passenger floor board and notice that the wiring harness was melting and not getting a good connection. so the a/c blower doesn't blow no air no more and i called a Chevy dealer and they said it would be about 685.00 for the wiring harness and about 2 hrs to install and i don't know what the rate would be on that.

i think gmc/Chevy should pay to fix this problem and have a recall on them cause who has that kind of money sitting around. i know i don't i live from paycheck to paycheck. if they are having all these problems with this they should do a recall and help us out with this. i don't even want to drive my truck in the summer cause its so hot down here in fl and the windows down don't cut it...

- , Zephyrhills, FL, USA

problem #3

Nov 302010

Sierra 1500 V6

  • Manual transmission
  • 90,000 miles

first you had to leave the temp adjustment in the blue or you heard a ticking noise now you have to leave in the red. what is this and how do i fix it or cam i?

- , Atkins, AR, USA

problem #2

Oct 222008

Sierra 1500

  • Automatic transmission
  • 89,000 miles

You put the controls on hot and the drivers side just blows cold. Took it to the dealer they fix it once. broke again know donn't have the money to fix it again

- , Chico, CA, USA

problem #1

Jun 012009

Sierra 1500 SLE 5.3L

  • Automatic transmission
  • 105,000 miles

Another common complaint that it seems nobody can provide an answer to. Driving down the road in the middle of summer when all of a sudden the air goes from nice and comfortable to blazing hot on the driver's side while remaning cold on the passenger side. Nobody can provide an answer for this problem. The dealership wants you to bring it in and of course it never acts up while they have it so they gig you for diagnostic time but can't find the problem or repair it. You know damn good and well that they know exactly what the problem is but laugh at you as you drive away pissed off. I've heard that the problem lies within the dual climate control head or the lower blend door actuator. I hate to start throwing money at a problem without actually knowing what the cause is but I also hate throwing money at a dealership that could really give a rats ass about my problems. Another fine piece of work from GM!

- , Kansas City, MO, USA

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