1993 GMC Suburban Owner's Manual - Page 230

Turn Signals When Towing a Trailer Whenyoutow atrailer,yourvehiclehas to haveadifferentturnsignal flasher and extra wiring. The green arrows on your instrument panel will flash wheneveryousignalaturnorlanechange.Properlyhookedup,thetrailer lightswillalsoflash,tellingotherdriversyou'reabout to turn,changelanes, or stop. Whentowing a trailer,thegreenarrowsonyourinstrumentpanelwillflashfor turnseven if thebulbsonthetrailerareburnedout.Thus,youmaythink It's importantto drivers behind you are seeing your signal when they are not. checkoccasionallytobesurethetrailerbulbsarestillworking. DrMng on Grades Reducespeedandshiftto a lowergear before youstartdown alongor to useyourbrakes steepdowngrade. If youdon'tshiftdown,youmighthave somuchthattheywouldgethotandnolongerworkwell. On alonguphillgrade,shiftdownandreduceyourspeedto 45 mph (90 kmk) orlesstoreducethepossibility of engineandtransmissionoverheating. If youhaveanautomatictransmission,youshoulduse D (or, as youneed to, alowergear)whentowingatrailer.Operatingyourvehicle in D whentowing a trailer will minimizeheatbuildupandextendthelife of yourtransmission. Or, if you haveamanualtransmissionwithfifthgearandyouaretowinga gear, justdriveinfourthgear (or, asyou trailer, it's better not to use fifth needto,alowergear). Parking on H i m You reallyshouldnotparkyourrigonahill. If somethinggoeswrong,your rig could starttomove.Peoplecanbeinjuredandbothyourvehicleandthe trailercan be damaged. But if you ever have to parkyourrigonahill,here'show 1. Applyyourregularbrakes,butdon'tshiftinto for a manual transmission. 2. Havesomeoneplacechocksunderthetrailerwheels. to doit: P (Park)yet,orintogear 3. Whenthewheelchocksare chocksabsorbtheload. in place,releasetheregularbrakesuntilthe 4. Reapplytheregularbrakes.Thenapplyyourparkingbrake,andthen shift to P (Park),or R (Reverse)for amanualtransmission. 5. If youhaveafour-wheel-drivevehicle,besurethetransfercase drivegear-not in N (Neutral). is in a 4-62