On 7/26/2013 2:15 PM, H. S. Teoh wrote:
I think most automatics lock the steering wheel upon power off (probably
as some kind of safety guard, maybe against inadvertent damage by some
parts that expect power to be running when the wheel is turned?).
It's an anti-theft feature.
I also use manual downshifting on my car (auto transmission) to force it
to slow down -- e.g., down a hill, when the automatic transmission will
often blindly shift to a high gear and you'll find yourself having to
burn up much of your brakes to keep the speed under control. My car has
a button that locks the maximum gear to 3rd, which is useful for keeping
within city street limits when going downhill. It also has gear
positions to force a switch to 2nd or 1st gear, though I rarely use
those since at lower speeds there's generally no need to bother with
them. In an emergency situation, forcing it to 1st gear would help
reduce the speed. (But it does take a few seconds before the auto
transmission kicks in to effect the switch -- and a few extra seconds at
high speed can be too long in an emergency situation.)
Although commonplace, it is poor practice to use the engine to slow the car down
(unless you're dealing with brake fade from overheating).
1. Brake pads are cheap compared with engine rebuilds.
2. Using the engine as a brake can cause unburned gas to wash the oil off of the
cylinder walls, resulting in excessive wear.
3. The engine is not designed to be a brake. Use the brakes. Brake pads are not
precious :-)
I think the one time when forcing 1st gear proved useful was when I had
to drive downhill after a heavy snowstorm -- you do *not* want to go any
higher in that situation otherwise you could easily lose friction and
slide down to a nasty crunch at the bottom. (Well, the general advice
is, don't drive in such conditions in the first place -- but then guys
like me are often rather foolhardy. :-P)
I prefer a manual trans in slippery conditions - more control.
