Noise from fan area of 2005 Chevrolet Traillazer

2005 CHEVROLET TRAILBLAZER
122,000 MILES • 5.0L • V8 • 4WD • AUTOMATIC
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JASONK_56
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Often hear a noise when driving and when let off of the gas I hear a rattling/spinning noise. Took to my mechanic and he put up on the lift with me inside and had me start engine and put in all wheel drive to replicate the noise. Isolated the noise to the fan area. Replaced the clutch fan but not the blades. Now when I start t-blazer in the morning, I hear a loud whirring noise until vehicle shifts up to third gear. Then when I let off gas I still hear original intermittent rattling/spinning noise. Looked in engine and I noticed that fan does have a wobble to it even though fan clutch is new. Called mechanic and he said it must be the fan blades. Since he replaced fan clutch and I still have the noise I want to be sure that the noise isn't something more sever. Also had leaking water pump replaced in 2012 when vehicle had 100,000 miles on it. Does this sound like the fan blades, or could it be something else like the water pump? When vehicle was on the lift they stood underneath and pinpointed noise to fan area and ruled out axles or drivetrain.
Apr 29, 2015 at 10:23 AM
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SATURNTECH9
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Its really hard for me to pin point a noise i cant hear or see anything your my ears and eyes.Are you sure the fan blade isnt hitting the fan shroud?
Apr 29, 2015 at 12:33 PM
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JASONK_56
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Fan blades are definitely hitting anything. They are a little wobbly but do not make contact with anything and are not loose. Noise only happens at certains and goes on and off with acceleration and deceleration.
Apr 30, 2015 at 7:46 AM
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JASONK_56
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Sorry, the blades are not hitting anything and aren't loose either.
Apr 30, 2015 at 9:34 AM
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SATURNTECH9
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Is there any play in the water pump shaft that would make the fan wobble and can make a rattling noise.
Apr 30, 2015 at 9:56 PM
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JASONK_56
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Replaced fan clutch and fan blades. Checked shroud for any signs of contact and water pump for any signs of play in shaft and all are negative. Noise still emanates from the front engine area when the speed is up over 25 mph and occurs intermittently. Any suggestions?
Jun 4, 2015 at 7:12 AM
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SATURNTECH9
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I just had a 2005 trail blazer with a noise in the fan area the fan blades tore up the fan shroud i had to replace the fan shroud and the noise was gone . without hearing the noise its hard to say what the noise is.So its a rattling spinning noise?
Jun 6, 2015 at 6:59 AM
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JASONK_56
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Yes its a fast rattling spinning noise...for lack of a better description its like the noise made by the wheel on "wheel of fortune" or the spinning noise at the beginning of the ozzy crazy train song if you are familiar with that.
Jun 16, 2015 at 7:58 AM
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SATURNTECH9
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Have you taken off the belt to see if the noise goes away when its making the noise.
Jun 17, 2015 at 7:17 PM
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JASONK_56
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How would a belt make that kind of noise?
Jun 18, 2015 at 11:37 AM
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SATURNTECH9
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No something the belt was spinning so when the belt is off and the noise stops then you can narrow it down to something that the belt is spinning.
Jun 18, 2015 at 12:30 PM
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JASONK_56
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Took to a Chevy dealer and he said its the rear differential. How can this noise sound like it is near the fan area?
Jun 29, 2015 at 10:35 AM
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SATURNTECH9
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I know sound can travel and sound like its coming from one area and actually be coming from a completely different area.But from the rear end to under the hood be really strange.
Jun 29, 2015 at 11:35 PM