When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I know the procedure but is there something specific to use to flush out the system
I have no idea if items like Coolant System Flush have a negative effect on LS1s, but I've stopped using them because they ate up three water pumps in a Honda I had. I changed the coolant in June, and in August I replaced the pump. Like I said, there may be no problem with LS1's, but I thought you might want a heads up about the possibility.
GB
The service manual says to use only water, for a flush it says just to cycle water through the system until it comes out clear (that is drain and refill with water several times). It say NOT to use a chemical flush.