I just replaced the v-belts to the alternator on my 1996 LX450. A much tougher job than working my old FJ40!!! Once installed and adjusted, I started the engine and the previously quiet engine was whirring big time. Bad at idle...worse when revved up to 2500...not so much after 3000 rpm. Definitely coming from the drive belt region. I thought (and was told by an auto parts saleman) it was the alternator front bearings??? We put a newly rebuilt alt on and got the same sound. The new belts are the ribbed back kind (Gates). The factory belts were smooth backed. Could that be the problem? The pulleys all look in line, deflection is w/in tolerance (1/4"). Seems like a stupid problem...but I can't figure it out. I've already junked the old belts, so I can't put them back on. Do I just get genuine Toyota belts from the local dealership? I read that flipping the belt around to reverse the direction might fix noisey belts.??? Help!