TM 10-3930-643-34 HYDRAULIC  SYSTEM  TROUBLESHOOTING  AND  MAINTENANCE. 12-17. Oscillation Cylinder (S/N 2000 and below). (Sheet 3 of 8) REMOVAL 6. Attach hoist and sling to cylinder assembly  (11). 7. Using a hammer and wooden dowel, remove two pins (10). Drive pins (10) out using care not to damage pins (10). 8. Using  a  hoist  and  sling,  remove cylinder  assembly  (11)  from  mounting brackets and place on a suitable work bench. 9. Remove hoist and sling. DISASSEMBLY 10. Using  a  spanner  wrench,  loosen retainer  (13)  from (11). NOTE Observe   positioning wipers  and  packings cylinder   assembly of  seals, when  removing them. Record  positioning,  as necessary,  for  proper  assembly. 11. Remove items 13 thru 27 as an assembly  from  cylinder  shell  (12). Go to sheet 4 12-154