AC/Heater for 05 Diesel's

LiftedHDRado · December 30, 2004

I just about a 2005 Chevy Silverado 2500HD Diesel 4x4 and everytime I turn on the AC/Heater it makes a whistle sound. As I crank up the ac/heater the whistle gets louder. Is this normal? I already took it to the dealer and they changed the ac/heater pump but dont think that was the problem...anyone out there ever heard of this before?

Jacqson · December 31, 2004

I just about a 2005 Chevy Silverado 2500HD Diesel 4x4 and everytime I turn on the AC/Heater it makes a whistle sound. As I crank up the ac/heater the whistle gets louder. Is this normal? I already took it to the dealer and they changed the ac/heater pump but dont think that was the problem...anyone out there ever heard of this before?

<{POST_SNAPBACK}>

Sounds to me like the fan motor which is the same motor for Heating and A/C. I had the same sounding problem on my work truck (01 HD) and when they changed the blower motor the whistling was gone. Hope this helps

Hutch · January 3, 2005

I'm glad you brought up this "whistling" issue. I have an '02 and it whistles, but only when I turn the temp control to heat. The whistle get louder and a little higher in pitch when I turn the fan speed up. Changing the distribution (upper vent, lower vent, defrost) makes no difference.

It sounds to me like something partially obstructing a vent door near the blower motor. Sometimes it does not make the noise. I cleaned my cabin filters and some leaves came out. How did leaves get to the filter? If they got to the filter, could they get past the filter and obstruct the heat door?

Hutch

Jacqson · January 4, 2005

I'm glad you brought up this "whistling" issue. I have an '02 and it whistles, but only when I turn the temp control to heat. The whistle get louder and a little higher in pitch when I turn the fan speed up. Changing the distribution (upper vent, lower vent, defrost) makes no difference.

It sounds to me like something partially obstructing a vent door near the blower motor. Sometimes it does not make the noise. I cleaned my cabin filters and some leaves came out. How did leaves get to the filter? If they got to the filter, could they get past the filter and obstruct the heat door?

Hutch

<{POST_SNAPBACK}>

That's really strange, but I don't think that anything like leaves could get past the filter because it is a HEPA type filter which filters things out like pollen and very small particles. Unless the filter was somehow installed improperly or not at all there is no way something the size of a leaf would get past it. Also it may not be the motor itself but maybe something close to the fan blades that may be stuck in there.

LiftedHDRado · January 4, 2005

I just took in my HD yesterday to the dealership because the first time I took it in they replaced the motor pump or whatever it is called and that never did fixed the whistle noise...so I took it back yesterday and they finally fixed it. It was something to do with the door sticking to the vent or something like that..so they had to fastened it up. The problem with mine was anything the ac/heater was on it would whistle..the whistle would get louder as i moved it to higher speeds...