When going downhill, lets say in manual gearbox, we are always on a lower gear. Most probably 3rd. As it gives greater control and it helps in engine braking and reduces the stress on the brakes when we slow down for a corner.
So, if gearbox holds on to D3 when going downhill for longer, then its a good thing. Same goes for uphill, If it changes like on flat road, then there are chances that engine hits low rpm and then again the box has to downshift.
So, if gearbox holds on to D3 when going downhill for longer, then its a good thing. Same goes for uphill, If it changes like on flat road, then there are chances that engine hits low rpm and then again the box has to downshift.