Alright i have searched for this and i can't find the answer. If there is knock retard is there always a SES or is it possible to have knock retard without the SES light? Also could u please post the GM part number of the LT4 KM. THanks

 

Knock retard doesnt throw a code.

PN is 16214681

 

If your going to get a knock module, the cheapest way i think is gmpartsdirect.com. $40 shipped

 

or Dal is about the same price and you know when he ships it you'll get it wiithin a few days.