This bulletin applies to 2025 Chevy Suburban and Tahoe vehicles as well as GMC Sierra and Yukon vehicles. Some customer may comment about a gurgling noise from the cooling system. The cause may be a cast-over concern in the plastic coolant surge tank.

Inspect the passages at the top of the surge tank for a restriction by using a blunt, round tipped probe tool, with a length of more than 2.05 inches. There may be slight casting leftover material that is restricting the hole. If the condition persists after cleaning/removing the restriction, replace the surge tank using P/N 84632822.