In a manual transmission car, when a driver wants to go below the speed the car travels at in first gear with no added gas using the gas pedal, my first driving instructor told me you ease off the clutch, reducing the amount of power from the engine transferred to the axle. [update - several people have since told me that this isn't a good practice, and it's not the only thing he taught me that has turned out to not be a great idea...]
In an automatic car, to achieve the same effect, you push the foot brake. This bugs me for two reasons:
- Is this constantly grinding the brakes? I'm in a city with bad traffic where I'm often crawling at 3mph with my foot on the foot brake. Should I be worried about excessive brake pad wear compared to what I'd expect in a manual?
- At first I couldn't understand why the car wasn't stalling - I now understand that automatic transmissions use fluid rather than the contact friction of clutches which allows slippage. This makes me wonder if what is actually happening is similar to a manual in that less power is transferred to the axle and it's not actually the brakes that are taking the strain?
Is driving at such slow speeds in an automatic putting extra strain on the brake pads compared to what a manual would be doing, and if not, why not?