Sonnax does not make total VB kits for the purpose of correcting inherent defects, VB correction kits.
Ford has different correction kits for each model of 5R55E, basically TSB part numbers. So check on what that Ford part number is, it could be the same kind of minor kit like the Sonnax part you refer to. Those are support parts, not the critical actual correction kits needed in all 5R55E's.
TransGo makes a correction kit for the 5R55E, as does Superior. The TransGo kit applies to all 5R55E's, every year model according to their literature.
Pick one actual VB correction kit to install. Also look at the available Sonnax support items, like the o-ring kits, and certain upgraded internal valves etc. Sonnax doesn't do VB shift or correction kits, they concentrate on individual components and circuits.
Sonnax not too long ago discovered a major cause of the 5R55E VB gaskets blowing out. The actual trans case moves/shifts/vibrates as internal pressures change. The gaskets seal different case channels from each other. If those channels move, eventually the gaskets wear out there. That is what has been happening, and Sonnax disclosed that, and their solution.
Has someone yet posted links and/or pictures to the Sonnax article about that solution? The answer is to install objects(set screws) up into those susceptible case channels, to hold them in place. Find the noted set screw sizes, and tap them up into the case where described. That will keep the trans case from shifting, and keep the gaskets from blowing out there.
