Proper Shiftiing
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2004 CLK320
Proper Shiftiing
I see a lot of people when driving an automatic, they would shift between D and R before the cars was completely stopped.
When I back out from my garage everyday, occasionally I would shift to D before the car was stopped.
Does this practice damage the transmission? Do modern transmissions have any build-in override mechanism to protect the transmissions?
When I back out from my garage everyday, occasionally I would shift to D before the car was stopped.
Does this practice damage the transmission? Do modern transmissions have any build-in override mechanism to protect the transmissions?
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2008 CLK550 Cab
There may something in the tranny to to prevent that from happening if the engine is revving, but I think as long as your foot is not gas and the engine is at idle speed, then there is enough slop in the nature of a torque converter to prevent damage.
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MBWorld Fanatic!
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2004 CLK320
I can safely say that the foot is on the brake but not sure if idle speed.
Thread Starter
MBWorld Fanatic!
Joined: Jan 2004
Posts: 2,200
Likes: 10
2004 CLK320
I can safely say that the foot is on the brake but not sure if idle speed.
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NO LONGER ACTIVE
A modern automatic transmission uses a combination of several drum gears and planetary gears that run within the drum. There are various sets of clutches that are engaged to selectively lock their drums from rotating. When that happens, the planetary gears inside stop "riding" the rotation of the drum and they start rotating themselves, so whatever is on the end of their shaft (another drum or another planetary set) starts rotating at a different speed. These combinations of drums engaged or not and planetary gears "riding" or "running" make up the gear ratios of the transmission. And of course on of the those planetary sets is gear in reverse, so when its drum stops, it has to rotate backward.
The gears themselves are pretty stout and can take harsh changes. What can't take a lot of slamming are the clutches. Every time you feel a hard thud, it's a clutch pack engaging to stop a drum that is under a good amount of torque load. This is not good for the clutches as it causes them to wear prematurely, and can even cause damage. It's best not to shift between drive and reverse except when stopped. This lets the torque converter cushion the load on the clutches.
The gears themselves are pretty stout and can take harsh changes. What can't take a lot of slamming are the clutches. Every time you feel a hard thud, it's a clutch pack engaging to stop a drum that is under a good amount of torque load. This is not good for the clutches as it causes them to wear prematurely, and can even cause damage. It's best not to shift between drive and reverse except when stopped. This lets the torque converter cushion the load on the clutches.
