The end plugs at the kick downshift control, manual low, and throttle downshift control valves become loose. This allows solenoid feed oil to exhaust and drop below 40-45 psi, which prevents the shift valves from stroking fully. Sonnax O-ringed end plug and checkball kit 37947-13K contains O-ringed end plugs for these three locations, which positively seal the circuit to prevent oil loss.

• O-Ringed end plugs positively seal the circuit to prevent oil loss
• End plugs have threaded ends for ease of installation and removal
• Kit contains 4 Torlon^® checkballs to replace lost or damaged originals
• Kit contains 4 L-shaped retainer pins to replace lost originals