GM Castech Cylinder Heads
Motor Rebuild Shops Tech Solutions: I’m sure most of you know by now about GM’s 4.8L and 5.3L Vortec Gen III and Gen IV V8 engines with Castech cylinder head castings. GM has sent shops Technical Service Bulletin (TSB) for Castech specific cylinder heads that are prone to cracking. GM’s TSB #06-06-01-019B covers 4.8L and 5.3L engines with VINs V, T, M, B, Z from 2001-2006. Motor rebuild shops be sure to check for signs of cracking if you encounter these engines/vehicles. And when pricing these jobs be sure to allow for additional costs. The conditions may result in a slow loss of coolant with no sign of leakage, or continued coolant loss after overheating the engine from a cooling system failure. Castech heads are identified by a symbol that looks like a battery on the casting.