5.7 whine

ChewyJ · January 13, 2002

I've just upgraded from a 1995 GMC 3/4 ton to a 1999 Chevrolet 1 ton crew cab. My new truck sounds like it has a super charger on it, and I know it doesn't. There is this high pitch whine that will fluxuate with rpm (me revving the vehicle). It almost sounds like an intake manifold leak, or air leak, but I don't see anything obvious. Since I'm used to the old 350, I don't know if this is a Vortec thing, or if I have an issue I need to discuss with the dealer.

Everything under the hood seems secure (i.e. air box/any visual vacuum lines).

Thanks for any help...

-Jason

95Yukon · January 13, 2002

Its possible it may need either the serpentine belt replaced or one of the bearings on the idler pulley or other pulleys could be going bad. Also the fan clutch can sometimes make that noise.

Import Hater · January 13, 2002

Quick way to check is just take off the serp belt and fire it up and see if the noise is gone. Usually a high pitched whine would come from a bad alternator, that would sound the most like a supercharger. An idler pulley would make more of a ticking noise. Water pump would sound like bunch of marbles. Power steering pump would have like a whining/groaning sound.

Rob

DigUout · January 14, 2002

I would check with the dealer first if it's still under warranty. If its whining higher as you rev the engine, sounds like a loose belt to me -

ChewyJ · January 14, 2002

Warranty is all gone....57K miles.

I love the truck, it has everything that I could have wanted. Probably bought it too quick from the dealer before looking at all of the little things....

I'm also faced with a water leak from the driver side floor board. I had hoped it was just wet from the detail, but no luck there. It looks like the truck has an aftermarket windshield, so maybe I'll just have someone reseal it (if they don't break it trying to get it out).

-Jason