I would think it would be rough on the rods first.

My EX had a 01 Silverado with the 4.3. It even said in the owners manual it would ping on 87 octane and that was OK! I told the service manager it was harmful and he told me nope! We ran 89 in it and didn't worry about it.

"The only thing to do for triumph of evil is for good men to do nothing"

"NUNQUAM NON PARATUS!"