2003 Subaru Impreza Owner's Manual - Page 246

Starting and operating WARNING Do not drive the vehicle with the selector lever in the "N" (neutral) position. Engine braking has no effect in this condition and the risk of an accident is consequently increased. B D (Drive) This position is for normal driving. The transmission automatically shifts into a suitable gear from 1st to 4th according to the vehicle speed and the acceleration you require. When more acceleration is required in this position, press the accelerator pedal fully to the floor and hold that position. The transmission will automatically downshift to 3rd, 2nd or 1st gear. When you release the pedal, the transmission will return to the original gear position. n While climbing a grade When driving up hill, undesired upshift to 4th gear is prevented from taking place when the accelerator pedal is released. This minimizes the chances of subsequent downshifting to a lower gear when accelerating again. This prevents repeated upshifting and downshifting resulting in a smoother operation of the vehicle. NOTE The transmission may downshift to 2nd or 1st gear, depending on the way the accelerator pedal is pressed to accelerate the vehicle again. n While going down a hill When descending a steep hill, depressing the brake pedal will cause the transmission to downshift to 3rd gear, thus applying engine braking. Reacceleration for a short time will cause the transmission to upshift normally. NOTE In some cases, depressing the brake pedal on a downhill grade does not result in an automatic downshift to 3rd gear. This can happen when the automatic transmission fluid temperature is very low, for example, during driving shortly after the vehicle has been parked for an extended period of time. When the ATF temperature has risen to a certain level, automatic downshift normally takes place. In the meantime, downshift manually for engine braking as required. Also, downshifting when braking downhill will not occur at speeds above approximately 48 mph (78 km/h). - CONTINUED - 7-17