This water crossover seal is designed to replace the coolant-port / steam-vent seals on GM Gen III and Gen IV LS engines where the OEM part number 12551933 was originally specified. The seal provides a reliable coolant-tight barrier at the water crossover ports, helping prevent leaks and maintain proper cooling system integrity. It is sold individually for applications requiring replacement of one or more seals during maintenance or repair work.

Brian Tooley Racing BTR51933 Features:

• Fitment: GM Gen III and Gen IV LS engines
• Replaces OEM water crossover / coolant port seal GM 12551933
• Designed to seal coolant passages at head‐to‐block crossover / vent ports
• Suitable for repair, rebuild or maintenance work requiring coolant system reseal
• Sold individually — purchase qty as required per engine

Brian Tooley Racing BTR51933 Notes:

• Sold individually; multiple units required to service a full engine coolant crossover system (typically one per coolant port)
• Ensure compatibility with your particular LS engine variant before installation