I have a 1999 v10. It has 215,000 miles on it. It started to make a noise that sounds kinda like a bearing noise but more dull. It only makes the noise when the engine is cold and on acceleration. Anyone have an idea? Thanks for the help

 

Well I played with it some more today. This is what I found. The noise starts at 2000 rpm. I took off the belt and it still made the noise.

 

If it seems to get better warm it is likely a piston or lifter noise. Bad bearings will be louder with the engine oil warm (thin).

 

Does the V-10 have hydraulic lifters? If so, throw some engine cleaner in to open up the oil passages.