I must admit my auto services have always been done by a mechanic with a flush machine, hook it up to the trans line and run the car, pumps old fluid out new fluid in, often takes 2x/3x times the fluid capacity to come out clean. I've also been using Penrite for years, engine, diff, gearboxes (auto and manual), brake fluid, greases. And Dave, as for why is TQ95 still on the shelf? Because Castrol is awful for updating their products, and representing and educating about their oils. I've been with Repco over 3 years now, and never seen a Castrol rep in either store I've worked in, and minimal product updates. Penrite I see a rep each fortnight, and continuous product improvements, new releases and product info.