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Old 22nd March 2009, 18:46   #76
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I had an AT OMHC (Original-model Honda Civic ) which was already old by the time I got it. I think it had a 1400cc engine, which was quite large for a small car. However it's performance from 0-30MPH was dismal. I just-about-always (unless I just wanted to roll) started in low gear and 'manually' changed up.

A few years later I had an AT Rover 620 (British-built Accord). Burst of speed needed to accelerate on a hill, or overtaking? flip the lever.

Have driven other autos too, for short periods and done the same. Over that period, I met one guy who said that manual changing causes more wear to the box. Just one. Otherwise, it is something I never heard, and always did.

The 'clutches' on both cars were hydraulic torque converters so no hard surfaces rubbing as in slipping the clutch on a manual. An AT can hold quite comfortably on an incline*.

DSG gear boxes are outside my experience, and likely to remain that way --- but I always read the manual, even for a car I'm hiring for a couple of days, so maybe, one day I'll be able to comment on them.

If they are really as fussy as you say, ImmortalZ, then I think all the advantage of an AT is lost. London driving at its worst: move 5 seconds, stop 30 seconds; move 5 seconds, stop 10 seconds; move 10 seconds, stop 60 seconds --- and how is one supposed to be able to predict? What makes an AT the clear winner in that situation is that all you do is take your foot on and off the brake, even not much acceleration is needed if on the flat.

Auto gearboxes should be all about convenience and simplicity, and should not need nursing. In fact, given that many will be sold to a market sector that is not buying manual because they could not really get the hang of a manual change, they should be capable of shrugging off the misuse of a car un-enthusiast. Autos are the norm in USA, aren;t they?


*EDIT: within reason! I guess energy has to go somewhere, so heat must be produced --- but handbrake hill starts are really unnecessary on light to moderate inclines

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Old 22nd March 2009, 19:03   #77
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Unfortunately Thad, the DSG boxes are complicated beasts which have a high rate of failure in all of the VW implementations. I do not know how they hold up in the Ferrari and other manufacturers' cars.

DSG boxes are more manual than your average torque converter based auto boxes with planetary gear sets et al. I saw the warning about changing to neutral at lights when I was cruising through the Porsche 911 Turbo pages and I can't seem to find it anymore.
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Old 22nd March 2009, 19:11   #78
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I think I've read something to that effect in other threads, possibly the one casting doubt on the quality of the current Passat.

Decades ago, the story was to beware automatics, as any decent mechanic could strip, fix and re-assemble a manual, but autos where boxes of extreme complexity, and very expensive when they failed. Maybe, after a long time of reliable, trouble-free autos, VAG have re-wound history on this one. Pity.
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Old 22nd March 2009, 19:38   #79
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Quote:
Originally Posted by Thad E Ginathom View Post
If that is true of your car, then that is some pretty weird gear box you have there!

This is absolutely not true of driving with automatic transmission. You can use the lever to force a downshift either for acceleration or braking any time you like. The automatic box itself should indeed, prevent a shift into a gear that is too low for the car's current speed.
True that you can downshift and the transmission will take care.

However, I was trying to say that it is better to make all selections when stationary. Certainly, the selections that are suicidal for the transmission if made when the car is moving are prevented, or 'mistake proofed' to some extent (Like selections into or out of P and R). However, the transmission is not designed to take constant lever selections when the car is moving, as if it were manual tranmission lever!
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Old 22nd March 2009, 21:10   #80
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... I think it is.

Well, regular, not constant.

Otherwise, it just doesn't make sense to me: you certainly would not start in a low gear and then stop to change to D. Nor would one stop, on beginning the descent of a steep hill, to change down.

Barring reports of new technology, which may or may not prove to be successful, as discussed above, I maintain that an AT is much more robust than a manual. Nothing prevents us from putting a manual into reverse when going forward --- although I admit that the noisy feedback probably stops us before too much damage is done.

But I guess we will have to agree to disagree on this.
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Old 22nd March 2009, 22:30   #81
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Quote:
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However, the transmission is not designed to take constant lever selections when the car is moving, as if it were manual tranmission lever!

I agree. Its an A/T - stop trying to drive it like a manual!

Moving to P wont hurt anything - but its a hassle and confuses drivers like me behind you. I get very nervous when I see the white reverse light flashing on the car in front!

From much experimentation - I've noticed that its quite hard to improve mileage with an auto/CVT. I say just drive normally and be done with it. Its not worth increasing your workload 5x while driving to get a 5% improvement.

Instead - drive it hard 4/5 times and walk the 5th
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Old 23rd March 2009, 00:34   #82
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All I'm trying to say, and maybe I gave the wrong impression, was that it gives you the choice.

If I had wanted to play gear-change all the time, I would have had a manual. D, 90% of the time, yes, that is what automatic is about. I've driven an auto with a manual mode; play for a while, get bored and go back to auto.

But when you want, or need them, 1 and 2 are there, and they are there to be used. There is nothing to worry about; you will not damage your car.

P, on the other hand, I'd agree, is for Park not Pause and it it is intended for parking and leaving the car, with the brakes on. It is not intended to take the weight of the car, and if used without brakes, that is not good.

Never, ever, have I heard that one should be stationery before making a selection, except same as manual: don't engage Reverse going forwards, don't engage a forward gear when going backwards.

That's it... I've had my say, and if you don't believe me, fair enough.
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Old 23rd March 2009, 11:27   #83
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Amen!

Automatics or manuals, man wants machine to remain tamed. Any attempt the other way round, and that's when man replaces it with 'better technology'!

Waiting for a transmission that can read my mind!
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Old 23rd March 2009, 11:43   #84
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Quote:
Originally Posted by Thad E Ginathom View Post
Never, ever, have I heard that one should be stationery before making a selection, except same as manual: don't engage Reverse going forwards, don't engage a forward gear when going backwards.
I'm just thinking out of the box here - why should I not do this?

The A/T torque converter uses a fluid clutch right? The worst thing that could happen is the fluid might heat up a bit more due to all that extra slowhing. Would shifting into D while the car is moving backwards at 3-4 mph damage the transmission? If so, what exactly will it damage?
If you do this, the car jerk a bit from all that turbulence in the fluid but it'll eventually start moving forward again and the thrust will become smooth after a few seconds.

I'm not saying one should do this - just wonder if any harm will actually be done. I am wondering if this has something to do with the 1-way fluid flow that torque converters are designed for?
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Old 23rd March 2009, 12:40   #85
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You are still trying to change to reverse or vice versa when the drive shaft is moving. It will cause damage the same way it does in a manual. This will be even more exacerbated in the A/T because the torque converter magnifies torque at low speeds.

The noises I hear from my car when I change from D to R even when the speedo shows 1KM/H makes me cringe. So I make sure it is fully stopped before changing directions (unless its an emergency) rather than risk damage.
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Old 23rd March 2009, 13:59   #86
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Yes, I do agree!

I know this is a bit extreme, but I knew someone who selected R while driving fast one day. His car would go backwards after that, but only with the most painful of grinding noises! Major repair!

So, whilst I still maintain that most auto boxes are fool-proof, they are not complete-idiot-proof!
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Old 23rd March 2009, 16:46   #87
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They do try to make them that way. You need to have the brakes pressed and the nifty lever/lock under the shifter enabled to let you move into R or P. I guess someone people still manage to blow these things up. God knows what will happen if one of these people try a manual.
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Old 23rd March 2009, 17:45   #88
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Guys, I want to know one thing. I have ended up in several arguments with my co-workers on this.

Is an automatic more fuel efficient than a manual or vice versa
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Old 23rd March 2009, 17:52   #89
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According to New advertisements, its better to switch off the engine if waiting at signal is more than 15 (yes 15) seconds.

So, IMO, if waiting is <15 sec, D + Brakes is the only sensible option.

Because >15 sec, switching off the engine is the best option (you have to out in P for starting again)
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Old 23rd March 2009, 18:18   #90
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Quote:
Originally Posted by thedreamcatcher View Post
Guys, I want to know one thing. I have ended up in several arguments with my co-workers on this.

Is an automatic more fuel efficient than a manual or vice versa
Slushboxes, which have torque converters are generally less efficient than their manual cousins. The rule of thumb is that they give 1-1.5KMPL less mileage than their manual cousins in the city. On the highways, A/Ts equipped with lockup clutches are are pretty comparable to manuals.

I'm not so sure on DSGs and CVTs. I suspect DSGs to be as efficient as manuals. CVTs, less efficient, although I do not know to what degree.
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