2005 Yamaha F90TR 90HP Outboards Factory Service Manual, Page 192Get this manual
Tilt cylinder and trim cylinder
S6D87450
Recommended power trim and tilt fluid: ATF Dexron II 5Install new O-ring, the joint, and the power trim and tilt motor by installing the bolts, then tightening them to the specified torque
NOTE: Apply grease to the balls from falling out of the cylinder installation8Install the trim cylinder end screw 8, and then tighten it to the specified torque
S6D87480
Trim cylinder wrench: YB-06175-2B Trim cylinder end screw 8: 90 Nm (9.0 kgfm, 66.4 ftlb)