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Discussion Starter #1
Not sure if you should do this or not, so wanted to ask. I know it's fine to float shift (shift up a gear without using the clutch) in non-synchronized transmission like those on heavy commercial trucks (I used to drive a 9spd Freightliner as my summer job when going to college incase anyone is wonderin how I know this), but is it bad for the synchronized tranny on the MS6? Especially in light of the awd drivetrain?

I've been doing it (upshifts only) in heavy traffic (laziness) and it works - is actually smoother shifting at low rpm than with the clutch - but have been wondering if I'm doing myself some longterm disservice. Anyone know for certain?

Thanks
 

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It will have the same effect on the MS6 as it will any other car. It will destroy your synchros.

So you can shift without the clutch now and have to double clutch later, or you can just drive like a normal person.

I guess in the end it evens out.
 

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Discussion Starter #4
It will have the same effect on the MS6 as it will any other car. It will destroy your synchros.

So you can shift without the clutch now and have to double clutch later, or you can just drive like a normal person.

I guess in the end it evens out.
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Heh, didn't think of it that way, been driving an auto-tranny F150 Supercrew for the last 5 years. That said, I'm betting that a clutch is a lot less than synchros, so maybe I ought to start using the clutch ;)
 

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i think it will wear your clutch out quicker but not sure, i did it with my honda civic sometimes also due to laziness. [/b]

ummm, let's see..........he's upshifting WITHOUT THE CLUTCH, correct? And because of this he's going to wear out the clutch quicker how..?????????? :huh:
 

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ummm, let's see..........he's upshifting WITHOUT THE CLUTCH, correct? And because of this he's going to wear out the clutch quicker how..?????????? :huh:
[/b]
+1, i dont get it either. when i used to have crappy cars, the clutch would start to go out and then i would start shifting without the clutch to make it last alot longer. I wouldnt advise doing it if it grinds, but if it doesnt grind when you do it, whats the harm?
 

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Heh, didn't think of it that way, been driving an auto-tranny F150 Supercrew for the last 5 years. That said, I'm betting that a clutch is a lot less than synchros, so maybe I ought to start using the clutch ;)
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:yesnod:

I wouldnt advise doing it if it grinds, but if it doesnt grind when you do it, whats the harm?
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Even if it doesn't grind, this is a perfect representation of your synchros: :swearin:
 

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Any manual can be shifted without the clutch. Upshifts and downshifts are both possible, as long as the driver properly sychronizes the transmission by controling the engine speed. This is the same technique used by drivers of non-sychronized transmissions, this is why double-clutching is necessary for those tranmissions.

If the clutch is not disengaged, then the layshaft speed cannot be controlled by the synchromesh, as the engine speed is still controlling the layshaft. Esentially, not disengaging the clutch prevents the synchromesh from being able to do its job of sychronizing the shifts.

As long as the clutchless shifts are done properly, tranmission wear should be very minimal. Unfortunately, getting it just right every time can be rather difficult, and the consequences for making a mistake can be bad. Worst case senario is probably one of the dog teeth on the engaging collar breaking off, which results in small metal chunks floating around in the transmission. It should be obvious to anyone why this will probably lead to a quick death of the transmission. Even if the worst case doesn't occur, improper timing/technique can lead to increased wear to the synchromesh and shifting linkage.

I used to mess around with clutchless shifting on some of my older vehicles, and developed some proficiency. However, I have completely stopped this practice, as there is no performance improvement, and the consequences of a mistake can be huge. On a new, expensive vehicle, I can't justify the risk.

If you want to learn some advanced shifting techniques, I suggest rev-matched and double-declutched downshifts. These can reduce clutch and synchromesh wear and result in smoother downshifts. These techniques can then be applied while breaking with a "heel-toe" shift, which is a great technique to master for competition driving.
 

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This was discussed recently on the msprotege.com forum as well. I gather that the consensus was that it doens't wear out the clutch, but rather the synchros instead. They also agreed that if you just let the transmission drop into the next gear when the revs are matched rather than holding it against the next gear with pressure then you would reduce the wear on the synchros.

I can't verify the truth of any of this information because I am NOT a transmission expert. This is simply the stuff discussed elsewhere.

R
 

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This was discussed recently on the msprotege.com forum as well. I gather that the consensus was that it doens't wear out the clutch, but rather the synchros instead. They also agreed that if you just let the transmission drop into the next gear when the revs are matched rather than holding it against the next gear with pressure then you would reduce the wear on the synchros.

I can't verify the truth of any of this information because I am NOT a transmission expert. This is simply the stuff discussed elsewhere.

R
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Well, if you do it PERFECTLY, there's supposedly close to no wear because you are doing the syncing for your transmission, but getting it PERFECT (or almost at least) every time is pretty hard.
 

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I do it from time to time and have so since I first learned to drive.

2-3 and 3-4 are the main ones that I do. You know you do it right when it almost falls out of gear and sucks itself into the next.

There is a definate sweet spot. (timing)
 

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I do it from time to time and have so since I first learned to drive.

2-3 and 3-4 are the main ones that I do. You know you do it right when it almost falls out of gear and sucks itself into the next.

There is a definate sweet spot. (timing)
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Thats what im saying, it falls into gear. I have been doing this for years and I have never had a car with a bad clutch. I had a truck one time that had a bad clutch when i bought it, but i drove it 15000 miles after it started slipping because of clutchless shifting. If you hit the (sweet spot) what does it matter?
 

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Thats what im saying, it falls into gear. I have been doing this for years and I have never had a car with a bad clutch.


If you hit the (sweet spot) what does it matter?
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Doing this will not affect the clutch in any way :slap:

You're not hitting the sweet spot, the synchros are helping you hit it. And they are working WAY harder than usual to do it.

Bottom Line: If you are doing this, STOP. This is not the way cars were designed to drive, this is not the way it tells you to drive in the manual. :irate:
 

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I said clutch but i meant transmission as far as grinding etc if you don't match it up right, long days at work suck

clutch in my civic went out and i had to do this for a few days, it sucked because I had to turn off the car to start out pretty much for getting it into first gear. down shifting was a PITA
 

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It will not hurt it at all unless you hear GRIND! Then of course it's bad. It actually save the clutch if you do it properly.
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Read the thread. It will save your clutch at the cost of your synchros. Which are MUCH more expensive to replace.
 

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It is bad. Because most people are not going to hit it right. Your syncros are made of a soft metel and bend a tiny bit from time to time while doing their job. At some point they will break. When this happens you will be screwed. By doing this type of shifting your making them work harder, sure if you hit the perfect spot each time youd be ok, but you will never hit the perfect spot everytime. Why screw with doing it, it doesnt help you, and it isnt going to save tons of clutch, assuming your treating your clutch ok to start with.
 

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Read the thread. It will save your clutch at the cost of your synchros. Which are MUCH more expensive to replace.
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Don't forget that the clutch "savings" will be minimal. The bulk of clutch wear occurs when slipping the clutch while starting out from a stop. Properly rev-matched shifts cause practically no clutch wear, as the flywheel and clutch are spinning at the same rate when the clutch is engaged.
 
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