1993 GMC Suburban Owner's Manual - Page 286

When to Check: A good timetohave it checkediswhentheengineoilischanged.However, thefluid in yourmanualtransmissiondoesn'trequirechanging. How to Check: Becausethisoperationcanbealittledifficult, you may choosetohavethis doneatyourdealershipServiceDepartment. If youdo it yourself,besuretofollowalltheinstructionshere, get afalsereading. or youcould Check the fluid level only when your engine is off, thevehicle is parked on a level place and the transmission is cool enoughforyoutorestyourfingers onthetransmissioncase. Then, follow these sf@ps: 1. Removethefillerplug. 2. Checkthatthelubricantlevel is up to the bottom ofthefillerplughole. 3. If thefluidlevelisgood,installtheplugandbesure it isfullyseated. the fluid level is low, add more fluid as described in thenext steps. 6-20 If