: Power Steering Whine / Hum



steve841
03-27-10, 09:49 AM
09 EXT with about 11K miles. The vehicle ... only when cold or warm, not hot, makes a whining/hum sound, usually from center to right turn and only when first driving lasting no more than 2 to 5 seconds.

Anyone know of this or if a TSB exists?

The only thing I found was :
Document ID# 1875699
2006 Chevrolet Chevy K Silverado - 4WD
Subject:Power Steering Whine Noise - keywords fluid gear hose idle pump turn #PIT4208 - (12/04/2006)



Models:2003-2007 Cadillac Escalade, ESV, EXT
2003-2007 Chevrolet Avalanche, Silverado, Silverado Classic, Suburban, Tahoe
2003-2007 GMC Sierra, Yukon, Yukon Denali, Yukon XL, Yukon XL Denali
2003-2007 Hummer H2



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:
Some owners may comment on a power steering pump whine noise. This whine noise is most commonly heard between idle and 2000 rpm coming from the power steering pump.

Recommendation/Instructions:
Reports of flushing and refilling the power steering system with Valvoline SynPower Power Steering Fluid have reduced or eliminated this noise. Valvoline SynPower Power Steering Fluid is a synthetic fluid and is available at most auto parts stores in quart size containers. In most case 3 or 4 quarts will be needed to flush and fill the system.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

dixit
03-28-10, 04:10 PM
Could be the pump bearings or for some reason fluid just not lubricating the pump initially but thats an odd case. If its only the first 2-5secs of start then to me sounds like it could be the bearings maybe or internal pump issues. Its also possible it could be the steering rack as you say its only from center to right and not other way. Pump usually dont care which way it turning because it just senses load and pumps fluid to the rack. So could very well be the rack.

That truck should be under warranty, take it into the dealer and have it looked at and fixed for no cost.

Dixit

revnate
04-10-10, 04:12 PM
I have the same power steering problem, only from center to right (technician says it's because the pump has greater distance/resistance to turn right). However, the whining sound usually starts after the car has warmed up. The dealership flushed the power steering and wants me to allow the fluid to cycle through for awhile. The technician said if it doesn't stop I'd need to have the pump replaced @ $300. Any ideas???

revnate
05-31-10, 12:37 AM
Had the steering pump replaced along with the belt. Still whines when making turns at around 20 mph. Any ideas?