I had a dakota that had the nv3550. It was kind of clunky. I refilled it with Lucas 75 140 and 1 bottle redline heavy shockproof gear oil. It was smooth as silk after that. I went from needing to clutch it on the up shift to being able to upshift under full throttle. I could burn the tires into fourth gear with that truck after the refill. Cryo treatment was mentioned earlier. As far as I know. Cryo is more of a wear treatment than a strength treatment. But I have be wrong before.