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I am aware that a car has to be at full stop in order to shift to reverse. Then I saw a video which was able to do a reverse without even stopping.

Insane parking https://www.youtube.com/watch?v=34IptxoHoYo

As most cars don't allow you to shift to reverse without stopping, is there an exiting transmission technology that can allow this?

  • I just want to point out that a '03 Impala, '98 Monte Carlo, '98 Dakota, '90 Bronco, '00 GMC 1500, '93 F-150, all automatics, can be shifted into reverse while going at least 3-5 mph forward. I tried once while doing 25 mph in the Bronco and it made a horrible grinding and killed the engine. In an hour I'll try it in '15 Rav4 and report back. – Zach Mierzejewski Feb 11 '16 at 1:40
  • And I thought most manuals could be shifted into reverse and then you let the clutch out very slowly to slow, stop, and go forward, but I might be mistaken here. – Zach Mierzejewski Feb 11 '16 at 1:41
  • @ZachMierzejewski, you can do this in manuals because the clutch is slipping. Yes, it will slow, stop, and change direction, but you are burning up that clutch plate very unnecessarily. If you shift into reverse while moving forward and let the clutch out, the clutch plate and the flywheel will be running against each other spinning in opposite directions. – Poisson Fish Feb 11 '16 at 20:53
  • @PoissonFish Thank you for pointing out the technicalities that my post lacked. ;) But, the question is phrased as if it is impossible (the lever won't move) to shift into reverse while moving and I wanted to point out that it is possible. – Zach Mierzejewski Feb 11 '16 at 21:28
  • @ZachMierzejewski - Just to add another data point - but in the opposite direction - a 1977 AMC Hornet automatic (wagon no less) can be driven in reverse at about 10 mph and then shifted into forward, which if you apply enough throttle at the shift, will result in a spectacular burnout! – Glen Yates Aug 10 '17 at 13:39
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There is a distinction that needs made between an automatic and a manual.

The majority of automatics will lock out reverse above a particular speed usually several miles an hour. If the car is below that speed reverse will engage while still moving forward.

In a manual transmission everything depends on if reverse is synchronized. If it's not then you will have a hard time jamming the transmission in gear. If it is synchronized then it's not that hard.

  • So to sum your answer up, all you need is a transmission with a Synchronized reverse? – Jomar Sevillejo Feb 11 '16 at 3:00
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    @JomarSevillejo most manuals manufactured in the past 20 years or so should have synchronizer gears. As long as you are rolling forward slowly it should be able to grip. – user4896 Feb 11 '16 at 4:53
  • The last manual car I was driving (2000 Celica GT) would not touch reverse unless you were dead stopped. That said, I don't know if the previous owner change anything (doubtful cause a trans is $$) because he did hack the gear selector in half to make it a "short shifter"... -_- – kyle_engineer Aug 10 '17 at 21:54
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In the case of the video you posted, I believe that driver just cut the clutch as he made the spin, and used the momentum he already had to back into the space and brake.

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I had a 1969 Chevy Malibu and we would do the opposite, back up fast, turn the wheel hard, slide the car so the front end comes around. While it is in motion, drop it into drive so that when the front end lines up with the direction of travel you straighten the wheel, hit the gas and you never stop. So you go from backing up, spin the car and keep on going!

Yes older cars would go into reverse at any speed but usually with great damage to the tranny. A friend of mine had a child that shifted his floor shift into reverse on the highway. Lots of smoke from the tires before he could get it back to drive. It didn't damage that one, at least not immediately!

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Yes, there is. Toyota's hybrid electric continuously variable transmission (eCVT) has all the time the only single gear (forward and reverse in the same) selected. Even though the power in the end comes from a gasoline engine and not from the battery in the long run, and even though this isn't a series-hybrid that would do mechanical-electric-mechanical conversion with all its losses, this system can switch to reverse gear at any speed, with no damage, at least in theory...

The reverse is just a reconfiguration of the computer controlling the transmission to apply backwards power, instead of forwards power.

Now, the question is whether it will allow you to do that at high speed or whether somebody has programmed something that would prevent doing so. I haven't tried shifting to reverse at high speed going forwards, but I can confirm that shifting to reverse going low speed forwards works, and it truly works in the way you would expect it to work: forwards momentum first decreases, the car comes to a stop and backwards momentum then increases. So, when you have the reverse gear selected and you are going forwards, it acts as an additional brake until you come to a full stop, after which it acts as a reverse gear.

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