We use Hi-Tach products in our race cars and other team vehicles.  We purchase race ready transmissions that come with a synthetic gear oil.  We were experiencing transmission problems until our gear mechanic suggested we go back to conventional gear oil mixed with Hi-Tach Oil Stabilizer.   We no longer have transmission problems and the wear patterns have returned to normal.

The team hauler has over 850,000 miles on it and my Dually has over 200,000 miles on it.  Zero failures and extended engine life.