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I have developed a certain shifting technique on my 2016 Toyota RAV4 hybrid. After reversing from the parking location, I change the gear to "D" from "R" while the car is still moving slowly rearwards. Because the car does not have an actual transmission (there is an electric power split device), I can do that. The effect is that when I change the gear to "D" while reversing, the car starts to accelerate forwards and is soon moving forwards. There's no need to come to a full stop before changing from "R" to "D" or vice versa. I know that on this car, doing so cannot lead to any harm due to the electric drive.

Now, let us suppose a car that has a conventional automatic gearbox. Can the gearbox be changed from "R" to "D" or vice versa when moving at a very slow speed? Can it cause harm to the gearbox? The answer to these questions has been already discussed on this site: Switching from Reverse to Drive - always stop completely?

However, automatic transmissions will be slowly displaced by new forms of transmission such as dual clutch gearbox or CVT.

Now, let us consider a car that has a dual clutch gearbox similar to Volkswagen's DSG. Is it possible to change from "R" to "D" or vice versa before coming to a full stop? Any possibility of harm (such as clutch wear) to the gearbox if doing so?

Or, let us consider a car that has a conventional CVT (not the electric CVT present in Toyota hybrids). Is it on these cars possible to switch from "R" to "D" or vice versa at slow speeds? Can the gearbox be harmed by doing so?

I'm not sure if this question should be split to two, as the answers to CVT and DSG case may be entirely different.

juhist
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As transmissions have become more and more computer controlled, many transmissions will not engage into a different direction unless the vehicle is stopped or more accurately, until the computer thinks the car is stopped. I can't say exactly which cars have the engagement inhibit programmed in, but it has become more common over the past ten years. In the cases where the car will allow the engagement to happen, it really depends on how fast you are moving. I have been known to shift from R to D before I am fully stopped once in a while without any problems, but people that plow parking lots tend to push the envelope on this one. They are going forward, reverse, forward, ect, to get the lot plowed. I have rebuilt many transmissions that were badly damaged due to this. On the GM light duty trucks they will actually destroy the case, in many instances. In my opinion, from 20 years of rebuilding transmissions, the most damage is from the mechanical sprag(one way clutch) banging the case lugs. The other clutch that applies is a controlled slip anyway and the torque converter (between engine and input of transmission) is designed to slip at low RPM. To wrap it up, you can do it depending on the vehicles programming, it can cause damage, but the damage is consistent with speed and how often it is done.

Eric Engel
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