when I drive my Tahoe and reach speeds of 60mph to 70mph the truck starts to make a combination whine/grind and it seems to be only when I accelerate or have my foot on the gas. It also comes and goes while driving at those speeds. The transmission does not seem to be slipping and the four wheel drive seems to be working ok. My mechanic has already replaced the rear u-joint, water pump, fan clutch, checked the front wheel bearings, the front u-joint and he is just stumped. He has ruled out it being tire related because it actually draws engine power as well. For a lack of better words, it goes from driving perfect to sounding like a four cylinder chain saw sounding motor. We are wondering if it could be some type of bearing that is driven by the belts, like the AC/heat or something.....why does it come and go and what could it be. Please help!!!
Nov 9, 2009 at 2:03 PM
