Automatic transmittions



Does it do any harm to drive a automatic shift car in any gear other that “D”?

That’s the question, here’s the context.

I generally do not like the way automatic transmissions shift gears. I like to keep the transmission engaged, and not let it float all over the place when accelerating or braking. If I will be traveling at 50 mph or over, of course I keep it in “D”. But if I’m on surface streets and the speed limit is less that 50 mph, I like to keep it in a lower gear appropriate for the speed I’m traveling. Also, when approaching a turn onto a side street, I like to down-shift in order to keep the transmission engaged through the turn, so that acceleration after the turn is positive and the transmission doesn’t have to fiddle with itself before it settles into a gear.

So back to the question. Does it do any harm to drive a automatic shift car in any gear other that “D”?


John in Gaithersburg, MD.


These days many luxury cars (not sure about Jag) have autos that can be shifted manually.

If the shift lever has detents for the gears it shouldn’t be harmful to use them.


John; your transmission is always “engaged”, and selects the best gear to be in appropriate to the speed. The 50 mph speed is right for “D” (and out of overdrive); you would be going in a lower gear going up a mountain pass, as we often have to do. The kickdown gear is for quick passing, or getting out of trouble. Again not to be used frequently since it causes excessive wear.

Please let the transmission “fiddle” with itself; it was designed to fiddle smartly and save itself from damage.

Whatever you are doing is not helping your transmission or you gas mileage and is distracting you from the task of driving.

In short, downshift by hand when you are in mountain terrain (real mountains) to get enough power on the uphill and to save the brakes from overheating on the downhill.