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Does a driver's acceleration practices substantially influence the wear on a car's automatic transmission? If a driver accelerates with a RPM > 3500 from stop, is this any "easier" on the automatic transmission than accelerating slowly at < 3000 RPM?

Over the long term, if a driver accelerates with a consistent pattern of acceleration, so that the timing of shifting up in gears is nearly the same, is the wear on the automatic transmission any different than if they were to vary it?

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Automatic transmissions are not mechanically linked to the engine (unlike manual transmissions), they are linked by your transmission fluid only. That gives us 3 things to consider:

Gears: Since they are mechanically linked to your wheels, your actual speed (not engine speed) is what dictates how fast the gears are spinning.

Torque converter: This is mechanically connected to your gears and linked through fluid to the engine. Higher engine speeds will make it spin faster, and that alone is unlikely to cause wear since we are talking about accelerating, we will only spend a small amount of time at high RPMs. Remaining at high RPMs may cause metal fatigue though, but I think something else may break first.

Engine: The RPMs are in the engine, therefore the engine is what is absorbing the vibrations, the torque and the heat. Higher RPMs mean more of all 3. Heat can be managed by the cooling system, but even with everything running optimally, there's a limit on how long you can maintain high RPMs before the temperature starts going up (you have a gauge for this). Many engines will auto-shutdown when the temperature gets too high in order to avoid engine damage. That leaves torque and vibration, and these 2 are likely to stress metal parts of the engine. Although there are rubber bushings and other related contraptions to absorb vibrations, they still contribute to wear, and the higher torque of higher RPMs is putting more strain on several components inside the engine, chiefly the crankshaft, piston rods and just about all the seals. Depending on the relative strength of each design, the weakest will let go first.

All that being said, don't worry about high RPMs too much. Drive the way you drive, and feel free to push high RPMs on occasion, just stay safely away from the redline on your tachometer. My redline is at 6900 RPMs, and I regularly push my engine to about 5000 RPMs when I really want to go, since high RPMs is where all my torque is. There is nothing special about my engine and I'm nearing 300,000 km on it. :)

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    How does your answer figure in lock up torque converters, which are prevalent in most vehicles today? – Pᴀᴜʟsᴛᴇʀ2 Jul 16 '16 at 19:57
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    @Pᴀᴜʟsᴛᴇʀ2 I am not entirely familiar with lock-up torque converters, although I do feel it as a "mystery gear" between 3rd and 4th on my vehicle. I know what they do, but not how they do it. :) – tlhIngan Jul 16 '16 at 20:30
  • @tlhIngan +1 not sure if you also answered the second part of my question since I don't understand how auto transmission works, but if I accelerate the same way all the time (for example, 0-40 mph in 10 sec from every stop) , will doing so over time wear out the same "areas" of gears, torque converter, and engine any faster than if I were to vary the way I accelerate? – T. Webster Jul 16 '16 at 23:45
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    @T.Webster No it won't :) The entire gear is used all the time and the entire torque converter too. Your engine computer will get used to how you drive and shift accordingly, as long as you keep your habbits the same. – tlhIngan Jul 17 '16 at 0:37

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