I have a 1991 Ford Superduty 460 auto. The starter worked, now it doesn't and it had a lifetime warranty (good). I got a new one and it grinds the first time and now just spins. Why????

It has 2 bolts, and no adjustment. I am thinking I have a defective starter, but what else could it be? Are there different starters for auto and manual transmissions? It the "throw" too short or too long?

I would like to know it is not my mistake before I return it

 

I know there are different starters for manual and auto small blocks in these trucks. I would guess the same goes for the 460.

 

I just ordered a starter for my 460 and had to specify manual transmission. I bet the throw is different.

 

Ringgear could have a bad spot, try barring the engine from the front and try the starter again.