I bought my 80 a couple of weeks ago. It was making a horrible undulating/oscillating whine from the front of the engine, sounding a like a bearing heading south. The noise was so loud, it could be heard probably 50 yards away. I used my mechanics stethescope to try and find the bad bearing, but could not find a culprit. Fearing this would probably necessitate a trip to a professional mechanic and cost me a bundle, I set out to educate myself as much as I could here on IH8MUD first. All the search engine gave me about whining noises was a mention of the Gates cogged belts being noisy. What the heck, I figured, I'll replace the belts first and see if that helps. I just got done with that job, and the truck sounds quiet and smooth now. The Toyota belts did the trick. Now I can spend the money I had set aside to fix the noise on a new exhaust (because now the danged whistle is the most prominent sound from my truck).