Alternator bracket bots broke off!

[mrein3]

Highsteel is correct in that you don't bottom out those bolts so you SHOULD be able to get them out easily. I usually use a flat blade screw driver and a hammer. Catch a burr of the broken bolt and tap it around until you get enough to grab with your fingers or a vise grips.

I had these exact same issues on my truck. What finally solved it was switching to a factory original water pump pully that matches the factory original crank pulley.

What was happening in my case - and probably in yours too - is that the pulley mismatch causes WILD vibrations at some rpms. In other words if you are on fast idle or slow idle, hood up you won't see the alternator bracket shake. But when you buzz it up to a certain rpm, the alternator looks like Elvis gyrating on stage.

Before the correct pulley I tried grade 5 bolts. Sheared them off. Then I tried grade 8 bolts. Yup. Those broke too. I tried various thicknesses of washers between the alternator bracket and the head and still managed to sheer them off. da-burb sold me a waterpump pulley off of a truck that still had it's GM-given configuration and all my problems went away.