BTR HEAD GASKET - 4.8/5.3/LS1 - SOLD INDIVIDUALLY - BTR89226 BTR has sourced our very own MLS head gasket that can be used on 4.8, 5.3, and 5.7 liter engines. This is a DIRECT REPLACEMENT for the LS1/LS6 GM head gaskets. This gasket has everything you know and love from the GM version: High quality, MLS construction, and it's produced by the same source as the OEM units!