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I say there is no such thing as uncontrolled acceleration. The reason for my comment is that I believe it is possible to shift any transmission to neutral at any speed and then you can bring the vehicle to a stop safely. Do not turn of the engine as you will lose power steering and control. A fellow told me that some of the newer transmissions prevented shifting to neutral at speeds.

Someone told me that some of the new Transmissions do not allow shifting out of gear to Neutral while moving. I want to know which vehicles have this transmission if in fact this is true. I personally do not believe this is a fact or possible. Thanks

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closed as unclear what you're asking by Nick C, Gabriel Mongeon, Rory Alsop, Larry Oct 9 '13 at 15:26

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1 Answer 1

First, I take issue with the premise of your question a little bit--just because one could hypothetically shift to neutral does not mean "there is no such thing as uncontrolled acceleration." How often do you think the typical driver of an automatic transmission car selects neutral? I would think that a driver could go years without having the need to shift to neutral. It is reasonable to expect a state of panic to take hold of a driver who is behind the wheel of a car that suddenly appears to accelerate on its own. In such a state of panic, it may be a stretch to expect this driver to think of shifting to neutral to halt the car's acceleration.

There are potentially a vast number of ways to bring a car that is accelerating on its own under control (use the brakes--they're more powerful than the engine, switch off the ignition, change to neutral, depress the clutch), the problem is thinking logically and reacting quickly enough to prevent a problem when you're suddenly in a panic.

That aside, to address your question. If a manual transmission car is accelerating HARD, as might happen if the accelerator was stuck full-on, it may require quite a bit of force to move the gear selector to neutral (unless the clutch was depressed first). When the transmission is loaded, it kind of holds itself in gear. The same may be true for some torque converter automatic transmissions, though I wouldn't know.

There are a variety of transmission types in use now:

  • Conventional Manual
  • Torque converter automatic ('contentional' automatic)
  • Computer-controlled manual transmissions with no clutch pedal (e.g VW/AUDI's DSG, BMW's SMG)
  • Continuously variable transmissions (CVTs)

While it might be physically, theoretically possible to shift all of these to neutral at any speed (i don't know that this is the case), modern transmissions have fancy electronic controls, and use a wide variety of levers, knobs, buttons and switches for mode selection. It may be possible that the control software does not allow the driver to select neutral at speed.

Likelier still is that the driver simply wouldn't be able to figure out how to do it quickly enough in an uncontrolled acceleration scenario.

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The question still has not been answered. –  user3754 Sep 27 '13 at 19:57
    
Still have not seen an answer to my question Some hyperbol but no answer –  user3754 Sep 29 '13 at 3:35
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I think mac answers your question quite clearly - there are situations where some types of transmission might not be able to be shifted to neutral at a given speed, either due to software restrictions or user inability. –  Nick C Sep 30 '13 at 10:17
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your question doesn't make much sense @user3754. mac hits the nail on the head. If you are looking to get different input, maybe you need to articulate your question better. –  Rory Alsop Sep 30 '13 at 13:29

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