| Source | Target | | gravity die-casting | fusione a gravità |
| gravity-feed fuel system | sistema di alimentazione a gravità del carburante |
| grease | lubrificare |
| grease box, oil can | latta dell'olio |
| grease cup | coppa di grasso |
| grease gun, greasing gun, lubricating gun | pistola lubrificante |
| grease nipple, lubricating fitting, lubrication nipple | nipplo di lubrificazione |
| grease point, greasing point, lubricating point | punto di ingrassaggio |
| grease retainer | conserva grasso |
| greasing pad, lubricating felt | tampone lubrificante |
| greasing pit, lubricating pit | cavità per la lubrificazione |
| greenhouse effect, hothouse effect | effetto serra |
| grey cast iron | ghisa grigia |
| grill guard, grille guard | proteggi-radiatore |
| grind | affilare |
| grind stone | mola |
| grinder, grinding machine, sander | macchina di rettifica |
| grinding paste, lapping component | pasta per la rettifica |
| grip brake, hand brake, pull-on brake, ratchet brake | freno a mano |
| grip, handling, road adhesion, road grip, road handling, roadability | comportamento su strada |
| gripper, grip pliers | pinza |
| grooved ball-bearing | cuscinetto con scanalatura a sfera |
| gross axle weight (GAW), gross axle weight rating (GAWR) | peso lordo dell'asse |
| gross combination weight (GCW) | peso lordo combinato |
| gross weight (GW), total weight | peso lordo |
| guarantee conditions, warranty conditions | condizioni di garanzia |
| guarantee period, warranty period | periodo di garanzia |
| guarantee, warranty | garanzia |
| gudgeon pin, piston pin, wrist pin | perno del pistone |
| gudgeon, mandrel, spindle | alberino |
| gudgeon-pin bearing | cuscinetto dello spinotto |
| gudgeon-pin boss, piston boss, piston-pin bore, piston-pin boss | alesaggio del perno del pistone |
| gudgeon-pin retainer, piston-pin retainer | fermo del perno del pistone |
| guide bar, slide bar | barra scorrevole |
| guide bearing, pilot bearing | cuscinetto centrante |
| guide line | linea guida |
| guide pulley, guide roller, idler, idler pulley | carrucola della guida |
| guide rail, slide rail, sliding rail | guida scorrevole |
| gull wing door, leaf door | porta ad ali di gabbiano |
| gulley emptier, sewage vehicle | camion cisterna acque di scolo |
| gusset | fazzoletto d'unione |
| hack saw | seghetto a mano per metalli |
| hair crack, hairline crack | incrinatura capillare |
| hairpin spring | molla a forcella |
| half axle | semiasse |
| half track | mezza pista |
| half-keystone ring | anello raschiaolio a pattini smussati convergenti |
| half-loop scavenging | lavaggio a mezzo cappio |
| half-round | semicircolare |
| half-throttle | mezza valvola a farfalla |
| hammer | martello |
| hammer drill | trapano elettropneumatico |
| hammer scale | scaglia di martellatura |
| hammering, water hammer | martellamento |
| hand control, hand operation, manual control, manual operation | controllo manuale |
| hand screw | vite manuale |
| hand throttle control, manual throttle | valvola a farfalla manuale |
| hand tools | utensili manuali |
| hand-brake cable, parking-brake cable | cavo del freno a mano |
| hand-brake control light, parking-brake control light | spia del freno a mano |
