Whining noise from rear of truck

[mark249]

I have a 2015 Colorado and I'm beginning to get a whining noise that sounds like it's coming from the rear of the truck. The noise begins around 45 mph and is the loudest between 50-60 mph. If you ease back on the gas pedal just a little it will "instantly" stop, touch the gas pedal and the sound will "instantly" comes back on again. The Chevy dealer has no idea where the noise is coming from except they believe it's coming from the rear of the truck. They said they could possibly find the problem but they would have to start pulling everything apart starting with the differential which could be costly and no guarantees that's where the sound is coming from. Has anyone experienced a problem like this before or have an idea what could be causing this whining sound? 

[newdude]

Sounds like its from the differential out back.  Gear whine or maybe bearing whine.  They will have to pull the cover and check for gear wear pattern, backlash, play in any bearings, etc. 

 

There typically should be some degree of whine even when new due to how the ring and pinion are set up.  The HD trucks make the most whine as they are set up for pulling heavy loads.

[RedGirl]

This might be a stretch, but worth exploring. Several years ago I had a 2009 Yukon Denali XL. I kept hearing this whining noise so a  friend of mine who was a mechanic went out with me and listened. He figured it was possibly the bearings and /or something inside the differential. Forgive me I don't know what any of these things are called, but he did a rear differential service and I think he replaced all the bearings and seals inside the differential and on the wheels. At the time the parts were 420.00 his price at the dealer for being a mechanic and charged me 320 to do the work in his home shop. The truck ran beautifully after that. I watched and helped clean what ever he told me to clean, but he took out all the gear things inside the differential and some cone shaped bearing thing. It was a lot of work. I'm guessing a dealer would charge 2000 for that if not more. I hope this is not disheartening. On the lighter side. My husband's current Colorado (2016) makes an awful noise.  I took it to my mechanic several months ago and he said the noise is coming from the tires don't worry. I'm a worry wart anyway so I insisted my husband take it to the dealer since it has a warranty still plus an extended warranty. They said the same thing it's the tires making that noise. It has whatever tires came on it when he bought it. That was today's verdict.  Will most likely sell soon because he wants something else..................................a freaking RV!!!! I'm going to loose my mind.