904 Steel Planetary Upgrade

Duane said
I would say it depends on the valve body and the line pressure he is planning to run. My tranzact valve body runs at 170 psi.
The recommended lever is 3.8 or 4.2. I know when I did the rebuild on my 47re in my diesel truck that initially I had the line pressure at 140 with a 4.2. The shifts were way to aggressive. Turning the line pressure down 15 pounds made the shifts firm but not aggressive.
Also in some applications the 5.0 lever aggravates shift overlap when the trans is in two gears at once just momentarily.
My current 904 build with aluminum front drum and the widest band available 1.75 inches I am going with a 3.8 for a clean shift. More is not always better with the levers. Just mho.

I actually finished and installed my build last month. I used the four pinion planets that were in it. I used regular steels and high energy green Alto frictions. 4.2 lever with a&a red lined cast bands front is smooth and rear is grooved. It has a late 76 valve body with a tf2 kit installed with all the mods for the hardest shifts. Put in a heavy duty accumulator spring, and a aluminum kickdown servo. Every bushing was also replaced. With the 2500 stall converter it's really smooth and crisp, not hard at all like I would have thought. It will snap your head and bark the tires at full throttle shifts though. All in all its its absolutely the best of both worlds.