I have a '07 Chevy Silverado, Z71, 5.3l V8 with approximately 58K miles. I recently noticed a "whining" noise coming from the engine, possibly the trannsmission/transfer case area. The noise is most noticeable when taking off from a stop or crusing between 35 to 45 mph. It sounds like the noise you hear when in four wheel drive (low) but it happens all of the time, even when in 2WD. I have no idea what it might be but am hoping it's not to major of a problem. Thanks for your help.