GM 6L80 and 6L90 1-2-3-4 pistons commonly crack due to cantilevered stress on the cast material. The OE part has been through several revisions in an attempt to correct this, but all OE versions are still chronically known to crack. Sonnax heavy duty 1-2-3-4 piston 104984-01 is made from stronger, billet aluminum and has superior design refinements that add additional strength to prevent breakage and deliver maximum performance.