I just put a replacement starter on my 396 and it still is pretty noisy(grinds occasionally). I hear people talk of "shimming" their starters. What does this do and how do you do it?

Thanks
Rod H.

Shimming it moves it further away from the ring gear. You need to get under the car and pull out the starter gear to see how it's engaging the ring gear to decide what needs to be done before you just start shimming. I've seen shim jobs that made it worse and ground off the gear on the starter cause it wasn't engaging and shimming made it worse. If too much clearance unshimmed you'll need to replace the starter nose with another and remeasure. Stock starters can definitely have some variation.