Sonnax MB-CP-11K has been replaced by Sonnax MB-CP-11KA
Similar to the MB-CP-10KA clutch release kit for most Mercedes 722.6, 722.9 converters, Sonnax clutch release kit MB-CP-11KA is designed to address the common complaint of poor torque converter clutch performance in 722.6, 722.9 units with three friction and steel clutch plates. Due to the additional friction and steel plate in these units, the clutch release springs in MB-CP-11KA (.510") are longer than those used in MB-CP-10KA (.310").
The most noticeable problem is cold engine stall on engagement, with other complaints such as shudder, engine lugging and clutch wear also possible.