My automatic (700 R4) makes a grinding noise when it's in first gear and as it shifts from first to second. It hadn't made this noise when up or downshifting to any other gears, just in first and to second. I was driving it today, and it once it started grinding in first as it shifted to second it kept making this sound, only quieter. It's such a strange grind, it's not as sharp sounding as grinding usually is. It's a softer sound, but not a whine. I can't come up with anything that would cause this. Has anyone had this happen to them before or have any ideas as to what it could be? Thanks, I appreciate any feedback.

 

If you have definately isolated the noise to the transmission. Your planetary gears are blown up, which most likely sent metal into your converter. So better get the trans overhauled asap before it locks up completly.
Josh
J.S. Performance