I hadn’t looked at the controlled load servo before as a possible upgrade point for firmer shifts. I couldn’t find much on forum searches either. I have been studying the Munroe and Hand books like crazy and the Munroe book has the mod in it but if there’s a good paragraph on function cause & effect I didn’t find it. All I did was inspect for cracks or scratches and reassemble with new seals in my last 727 build.

Looking at the parts and y’all’s mods what I’m seeing is the later servo is made more like a hydraulic lifter? So I guess pressure would bleed in and out of that little hole and create a cushion of oil for the apply rod (wrong name? Is it piston, retainer, rod?) to ride on?

So shimming it would eliminate travel and defeating the hole would eliminate oil pressure below the rod base? Either way the lower piston would have the apply rod in direct contact and could probably release faster.

Couple questions- first are there any changes that would need to ‘agree’ with this mod? I’m guessing the rest of the timing could only be improved with a faster 2nd gear release as another gear applies?

Second- how would pressure even get under the rod in any meaningful way to create an oil cushion in the first place? Doesn’t the lower piston with all its surface area apply quickly enough to take all of the KD lever’s travel before pressure could flood under the rod?

I’m getting closer to actually wrapping my brain around all these functions- the more I learn it all seems simpler.

Thanks

Radar