With many of the Hydramatic transmissions we take in (see pictures), the parts are extensively varnished and difficult to clean without special cleaning equipment. Some transmissions have sat in a barn, field or salvage yard for decades and these can look to be in very poor condition. Some owners think that these units cannot be brought back to life - but we disagree! Thermal-Cleaning, the cleaning process we use on Hydramatic transmissions, is different than for cleaning an engine block. With an engine, the block and heads are heated in a flame-oven to burn off debris. With a transmission, which contains aluminum, brass, stainless, and other soft metals, the cleaning process should NOT be harmful to the components. Classic Hydramatic cleans parts in a special high-temperature high-PH detergent water jet bath that deep cleans the parts but does not harm soft metals. From the pressure washer the parts are final brush-cleaned in a second detergent tank to ensure that your Hydramatic parts are fully clean. Case parts are then painted, sensitive components such as valve bodies and governors are disassembled and hand cleaned, and a final inspection is completed. Thermal cleaning is an additional cost and is required with older transmissions.