Recently my truck has started to make a whining noise after startup...engine running at idle and what sounds to be a bearing going bad. After I apply the accelerator the whining increases (similar to the sound of a blower on a custom car)....the noise sometimes lasts a few seconds or minutes after I press the accelerator at different pressures and it will be fine and noise goes away for the rest of the day. Has anyone experienced this problem? My thoughts are the alternator is starting to go bad (no dash lights yet) or an idler pully is due to be replaced.. Anyone with good solutions?