[BigD9146gt]

Back when i did use the synthetic, the trans was on its way to needing new syncros. However, everytime i've driven a car with a 901 gear box running sythetic, double clutching was better because the syncros were too slippery, there was no bite for the dog teeth on the selector rings. Once i drained the synthetic out and replaced with swepco, it was like night and day. Granted, at the time it still needed a rebuild, i comfortly got several thousand miles out of it before overhauling it.