37-SL-27-152 STABILIZER TRIM MOTOR IMPROVEMENTS. SERVICE LETTER MOS 27-JUL-2000 - St 737-SL-27-153 TRAILING EDGE FLAP TORQUE TUBE COUPLING AND U-JOINT LUBRICATION. SERVICE LETTER MOS 03-OCT-2000 - (s) St 737-SL-27-154 REPLACEMENT OF ELEVATOR OUTPUT TORQUE TUBE CONTROL CRANK BEARING. SERVICE LE