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Discussion Starter #1
Forgive me if this a stupid question as I'm still getting use to driving with a manual tranny. I notice that when I'm slowing down (for sake of example lets say I'm in fourth gear before I start to slow) if I depress and hold the clutch in and try to shift into first (while the clutch is in) I find shifting from any higher gear to first gear while moving is a little stiffer/more difficult than while at a stop. Am I doing something wrong? Should I just put the car in neutral and then brake rather than depress the clutch and shift into first knowing I'll need to be in first once I stop? I don't want to hurt my car, and I know the tranny is new, so maybe it will loosen up? Once stopped shift from any gear into first is smooth as glass....just curious what your thoughts are.
 

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Replying to Topic 'Question about downshifting'

No this is as it's supposed to be.

The reason is that a manual trannie has something called synchronisation rings that has the purpose of synchronising the speed of the two gear-wheels that are going to join.

If there was no such gear ring, the trannie would explode if you moved the driving gear-wheel against a completely still gear-wheel.

Also: The rpm you force your car into when you are in fourth gear and wish to push in the first gear could be potentially harmful. So: the faster you go, the harder to push the shifter in place, this is to avoid you pushing it into first at 90 mph. (You wouldn't want to do that...):D
 

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Replying to Topic 'Question about downshifting'

All the cars I have driven so far (VW Polo/Golf/Passat, Audi 80, Opel Astra) had some kind of a locking mechanism that won't let you shift into first gear (at least not too easily) while the car is moving.

As far as I know, the most economic way to come to a stop is to stay in as high a gear as possible for as long as possible. When you're ready to stop, depress the clutch and brake. Shift into first after you've stopped. You're not going to need first gear unless you come to a complete stop anyway. If the lights turn green while you're still moving, you're going to want to be at least in second gear.
 

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Replying to Topic 'Question about downshifting'

OH, Brillo, for clarity:

Never EVER shift a manual as you do an automatic. Downshift only one gear at a time, and if it feels forced, don't downshift!!!

As said: otherwise, we may have to weep a while for you synchros. And you may have to weep while your car is at the shop with a wrecked gearbox. Be careful!
 

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Replying to Topic 'Question about downshifting'

Thankfully, I'm not going fast when I did this, I've never gotten any weird noises or vibrations so I guess everything is ok. I'll keep your thoughts in mind from now on. This isn't something I did all the time, but it was a thought I had on the way to work. Speaking of safety features, I'm assuming our cars have both a rev limiter (never had to find out as I haven't gone over 5000 rpm yet) and a locking mechanizm to prevent the car from being shifted into reverse will moving (such as a missed shift to fourth gear).
 

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Replying to Topic 'Question about downshifting'

Good to hear. And yes: it has rev limiter as well as the locking mechanism for the reverse.
 

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Replying to Topic 'Question about downshifting'

For future reference, how would you know if you had prblems with your synchros?
 

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Replying to Topic 'Question about downshifting'

QUOTE
For future reference, how would you know if you had prblems with your synchros?[/b]

It would be VERY difficult to shift or you couldnt shift at all.....this might be preceded by lots of clatter/metal noise leading up to the eventual failure of the syncros.....


Nikolas
 

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Replying to Topic 'Question about downshifting'

ouch man! :) you can slow down by just shifting into neutral and using the brake. but i recommend always staying in gear, since you never know if you need to avoid an accident by stepping on the gas. when you do downshift, i was taught that the best method is to go in sequence and don't skip gears. my 2 cents
 

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Replying to Topic 'Question about downshifting'

I am taught this at driving school:

Drive on high gears until you get down to... never said it specicaly but I guess, around 30 km/h, then go to second gear and engine brake until you have to applie normal brake to make a normal nice stop. When stopped. Then enter first gear.

I tend to feel that it works better just pressing the clutch, let the car role until you need to begin braking... And then when stopped, enter first gear.

On the 6 though you can to a full stop and start on second. I normaly don't do it if it's other cars behind or it's importent that I get moving when I'm supposed to, at lights and such. But if it's just a stop sign it's quite safe (the car CAN stall if appling to little gas - don't wanna burn rubber :)). If the initial launch works fine its feels safer to start on second, since, if I cross a big road, I don't have to take a hand of the whell and shift in the middle of the road. Just push the pedal. :)
 

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Replying to Topic 'Question about downshifting'

The point of engine braking is not to cause too much wear on the brakes. This is especially important on a car like the 6 where all wheels have disc brakes. (This means hand brakes use the same brakes).

If you drive in a very terrain with lots of ups 'n' downs, braking without using engine brakes may cause brakes to overheat. This will cause total brake collapse. In a mountain nation like Norway for example this is extremely important. Many death accidents have happened because people didn't realize this.

For normal terrain, the only advantage of engine braking is not wearing out brakes prematurely.
 

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Replying to Topic 'Question about downshifting'

Many experts now say that you shouldn't use engine braking except when absolutely necessary. Back in the day when all you had was drum brakes, you could experience brake fade going down one long hill. Engine braking was important. Nowadays though you have many cars with 4-wheel discs, and improved brake pad technology. Braking causes wear. Period. Would you rather wear out your brake pads which are designed to be replaced cheaply, or wear out your transmission and engine? It's that simple. For everyday driving, you should push in the clutch, then sequentially downshift without releasing the clutch. That way if you need to accelerate, you can rev match (blip the throttle) and go. You should never downshift into first above approximately ten miles per hour.
 

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Replying to Topic 'Question about downshifting'

I don't quite agree. Even disc brakes can overheat and leave you without brakes. But for everday use, it's not necessary to engine brake. It's true this causes wear in the engine instead.
 

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Replying to Topic 'Question about downshifting'

If you're driving around San Francisco, perhaps you could get disc brakes to fade. Of course in extreme driving conditions, many factors come into play. That's why I said "when absolutely necessary". Driving on the track? Engine braking necessary. Driving LIKE you're on the track? Same. But I challenge anyone to make their brakes fade in everyday driving. You would have to totally abuse the car to make the brakes fade. This challenge doesn't apply to anyone with crappy brakes or an SUV.
 

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Replying to Topic 'Question about downshifting'

Actually, you can skip gears while downshifting if you know how to double clutch. In fact, double clutching is the best way to spare your synchros.

Before I explain what double shifting is, you may want to read this:
http://www.howstuffworks.com/category.htm?cat=Transm
and
http://www.howstuffworks.com/transmission.htm

While double clutching is not very useful for upshifting in a normal car, I find that it is a very good technique for downshifting. It can be used when slowing down to take a turn or when you need to downshift to get extra power for passing people on the highway. You will find that your shifts will be quicker and that next to no strain will be put on your synchros because your gears will engage almost instantaneously.

Here is how it works. Suppose that you want to go from 4th gear to 2nd gear. In double-clutching, you first push the clutch pedal in once to disengage the engine from the transmission and shift into neutral. Then you release the clutch pedal and rev the engine to the "right speed." The right speed is the rpm value at which the engine would go if your car was engaged in second gear and going at your actual speed. The idea is to get the transmission's gears rotating at the right speed to eliminate the need for synchros to do their work. Then you push the clutch pedal in again and shift. You will notice next to no resistance. At every gear change you have to press and release the clutch twice, hence the name "double-clutching."

This technique is a little hard to master at first and I don't suggest you try it before you feel comfortable driving a car with a manual transmission. Anyway, don't sweat it. Today's manual transmissions are very reliable and it really takes some abuse to wear them down.

Next lesson: shifting without clutching. ;)
 

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Replying to Topic 'Question about downshifting'

QUOTE
Originally posted by kenoka

This challenge doesn't apply to anyone with crappy brakes or an SUV.  [/b]
Doesn't bather owners of the 6 then ;)
 

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Replying to Topic 'Question about downshifting'

QUOTE
Next lesson: shifting without clutching.  ;)[/b]
Oh man, the first time someone showed me that I nearly made in my pants but he was all like "Trust Me" and it worked. I did it once to appease him and have never tried it since. Dont trust myself enough...
 

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Replying to Topic 'Question about downshifting'

I think engine-braking is fun. I go up and down hills watching other cars constantly use their brakes, when I never need mine. Makes me feel better than everyone else :)

And I drive an automatic. I like that "overdrive off" button!
 
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