I don't mess with auto's too much anymore, but since I'm getting ready to do some work on my truck, it kicked my brain into gear. My truck has a 46RE. Same basic hydraulic design as the A413. I'm getting to install the upgraded Sonnax 2nd gear servo and accumulator. Knowing that the A413 suffers from the same shift timing issues as the A904 based trannies and knowing/reading what these 2 hard parts help with, I was wondering #1 if these parts would fit the A413, and #2 if anyone had tried to apply the same principles as these parts if they aren't the same? Currently the way to improve shifting and 2nd gear holding is to increase line pressure and maybe install a bigger ratio actuator arm (which can cause binding issues). The reason for this is to compensate for internal pressure leakage, mostly. These new parts have a better sealing design and the servo is larger in area, so it increases holding power without messing with lever arms.

Anyway, this wasn't an option back when I built my A413 a long time ago (that I knew of), but it *might* be an option now of these parts would fit.