Whining Noise

excaliboar · July 17, 2011

My '99 GMC Z71 ext cab has developed a whining noise that I can't pin down. When driving it sounds like it's coming from the front. Had the ball joints & pitman arms replaced back in the winter & ran a few days in 4WD in the snow w/o any problems. It's not a daily driver, but I just now started noticing the noise. It's a high pitched whine that increases in pitch as rpm's increase. Any ideas?

blacksierra01 · July 17, 2011

Belt Whine? Does it only happen as you are driving, or when ideling too?

excaliboar · July 17, 2011

Doesn't really happen while idling, but reved it up while parked & listened under hood. Think I may be getting lucky & it being alternator rather than something in front end.

desrtrat · July 17, 2011

also check your PS pump. been known to whine when low on fluid, or starting to go out..

greentourismo · July 18, 2011

I had the same problem with the whining in my truck, I started leaving my wife at home and the problem suddenly stopped

cariveau · July 18, 2011

I had the same noise you describe in a 2004 Grand Cherokee that I thought for sure was coming from the tranny. The mistake I made was bringing it to a transmission shop stating that I thought it was coming from the trans.

They started at the transmission where everything looked good. Did a flush and new filter.

Went on to the transfer case... Changed the drive chain.

Went to the front diff... Rebuilt the Dana 36.

Then finally said they could pin point it to the left wheel bearing! I haggled on the bill and they did end up treating me fair. I was pissed as I used to fix repairables and have heard many bad wheel bearings plus I could have fixed it at home.

My exact issue:

-whine would not start until 30mph, seemed... like it was when it shifted to second.

-it was so load that it would echo off houses.

-noise was repeatable up on jack stands.

-pitch also increased with speed / and or RPMs

If the wheel bearings are original it would hurt to change them both. My 2 cents. Ryan

excaliboar · July 19, 2011

Definately not the alternator, power steering pump, or belt. Only does it while the truck is rolling. Pretty sure it's coming from the front. Guess i'm gonna have to take it in & have it put on a lift. Maybe I'll be lucky enough to be a paranoid moron & it's just tire noise.

excaliboar · July 26, 2011

I'm keeping my finger's crossed it's a wheel bearing, but I had it checked out by a local shop who says the noise if coming from the transfer case. Dropped it off w/another guy for a second look just to be sure.

If it is the transfer case, what kind of $'s are we talking about? I've already had to rebuild the tranny & front end. I'm about tired of putting money into this darn thing.