help diagnose whining noise

Do you have a mechanic's stethoscope. The less expensive ones are very reasonable. I think I paid $8.00 at HF for mine. I had a similar noise once, and it wound up being the bearings in my alternator. One would expect a grumbling noise, but it was more of a high pitched squealing or whining. Anyway, with a stethoscope, you can touch things one at a time and very likely track down that noise.