06' Fan Clutch/Hvac problem

[wcjp]

06' Mega G56 4x4 w/30k miles. Just started last week. When AC or heat is on the fan clutch is making some weird sound/vibration. Originally thought it was a Ujoint problem. Any ideas? I have a dealer appt on Thursday for the wife to drop off. Nearest dealer to my work (5min) is unreliable. Don't want to take any time off. I've also found most counterman useless. Would like any ideas.

 

[nps]

When AC or heat is on the fan clutch is making some weird sound/vibration.

I don't understand how the heat being on could cause the fan clutch to make noise. If you need heat, the outside temps should be pretty low.

 

[wcjp]

I use defrost in the morning. The AC runs when the truck is in defrost. After clearing the windshield I switch to defrost/floor. I like constant flowing air. Traffic is so bad I keep the windows up to reduce the noise level of the big rigs.



Problem happens when the engine is both hot and cold. Everytime the fan engages the I feel the vibration/hear the noise. With the hood up the airflow definitely increases.

 

[MPletchetero]

Are you sure you're not hearing the "clunk" sound of the A/C clutch engaging?Mine gets pretty loud when the A/C compressor is cycling.

 

[wcjp]

Problem started a week ago. Never felt it before. I've used the AC previous to last week. I've been using the defrost all winter long.

 

[MMeier]

Does the compressor stay engaged, or does it cycle off and on every few seconds?

 

[Johnstra]

I've noticed my compressor cycling every 15-30 seconds. What does that mean?

-john

 

[wcjp]

Wife dropped off the truck today. Parts have been ordered. Won't know the problem until tomorrow afternoon.

 

[MMeier]

Wife dropped off the truck today. Parts have been ordered. Won't know the problem until tomorrow afternoon.

What was the problem?

 

[wcjp]

Dealer claims it the Fan Clutch assembly hitting the metal guard holding the wires. The Fan Clutch Assembly is on backorder. I say the tech has no idea what's wrong. If the Fan was hitting the guard why doesn't it do this all the time. The fan is always turning. But, only hits when the AC or heater is turned on. Somethings not right. Towing out of town this weekend. If I called the dealership at all this week my truck wouldn't be ready in time. Will call for next week appt.

 

[Ben S]

I noticed mine doing this last week when the ambient temps hit the high 90s and my dealer checked mine when servicing my recirc door HVAC system. He said it was because the compressor was working harder because of the high ambient temps and that nothing was wrong.



We'll see... . please keep us informed of how yours turns out.



BEn

 

[wcjp]

Mine has done this with outside temps in the low 70's. Called dealer yesterday. Part is in but they never called to schedule an appt. Truck goes in next Tuesday. Also asked them to look at Driver rear window not going down all the way (1/2"), rear floor vent blows warm air and the passgenger front window regulator they recently replaced sounds buzzy during operation.

 

[wcjp]

Fan clutch assembly was replaced. Still have the thunk. Wife dropped off/picked up truck. I'll have to take some time off to get it fixed.