I am reversing. While the car is still moving backwards, I switch gears from R to D, and press the accelerator to start moving forward. After a bit the car stops going backward, and starts moving forward.

My dad always told me that I should wait for the car to come to a complete stop before switching from R to D. He said that unless I did this, I would be damaging my engine. Is he correct? (Note that I'm going at extremely low speeds during this entire switch).

  • Does this answer your question? While the question isn't exactly the same, the effects are. You father is almost correct ... it will damage the transmission, not the engine. Mar 25 '15 at 10:45
  • I don't think it answers my question. That answer seems to apply if the engine is revving. In my example, the car is moving due to existing momentum, but the engine isn't revving. Mar 25 '15 at 16:50

In newer automatic cars, you won't be hurting the engine by switching from reverse to drive because the car will wait in neutral before actually going into gear. So if you don't have this feature, you could potentially damage things connected to the drivetrain by putting so much force on the torque converter.

  • Thanks. Next time, while my car is moving backwards, I will switch to D and press the accelerator. If my car has the feature you mention, my car should wait until it comes to a complete stop before accelerating forward? Mar 26 '15 at 4:16
  • If you shift gears while you're going under 10km, you won't be wearing anything out more than you otherwise would. The transmission and torque converter are designed to handle that kind of stress.
    – Sterling
    Mar 26 '15 at 6:34
  • @Sterling ... do you have any references behind what you are saying? Mar 26 '15 at 10:10
  • My reference is my ex who mentored me in how manual motors work. We went over some diagrams together. It's far from a professional reference, so I may not be entirely correct.
    – Sterling
    Apr 7 '15 at 10:39

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