Over the years, Sol-gel has been widely used in aerospace industry for surface treatment process in preparation of adhesive bonded repair to aircraft. It plays a crucial role in the process of bonded repair of aircraft as a chemical linkage between adhesive bonded repair and damaged metallic structure of aircraft. As a chemical linkage, it produces strong and durable bond between metal and organic adhesive (Thermoplastics) which improves the overall strength in adhesive bonded repair to aircraft. In this paper, both conventional and newly formulated sol-gel will be subjected under Wedge Test (ASTM D 3762-03) to examine its durability. This would be a crucial milestone if the durability of the newly formulated sol-gel is higher than conventional sol-gel. Cost of repair would be able to reduce as serviceability of the aircraft increase. Keywords: Sol Gel, Chemical linkage, Bonding Strength, Shear strength