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Old 08-07-2008, 12:30 AM   #1 (permalink)
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Am I hurting my clutch when I downshift without revving up?

I have a 2008 Civic 5-speed, and I don't want to inflict undue wear and tear on it. I am wondering if my downshifting is excessively harmful to my clutch. I know not to do bad things like slipping the clutch or riding it, so no worries there.

Let's say I'm going about 25mph and decide I want to downshift into 2nd to decelerate while zeroing fuel usage. Is it kosher to just clutch in, switch to 2nd, and take the clutch out without giving it any gas to up the rpms to the appropriate level? I do it fairly gently so there is no jerking, just a smooth slowerness. So basically I am wondering if making the clutch up the revs from about 800 to maybe 2800 without giving it any gas is bad. I know this is awkwardly worded...but thanks for any help!


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Old 08-07-2008, 01:56 AM   #2 (permalink)
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I do that all the time. Usually my cut-offs are: 3rd @ 60 mph, and 2nd @ 40 mph. Yes, the needle jumps to 4000+ rpms, but with the Civic it doesn't seem to hurt it as much as it would in a "rougher" revving engine. Sometimes I rev the engine trying to match the revs to the speed, so there is no "slipping" in the clutch. I am getting better at it, but that doesn't save fuel unless you then let the car roll for a long distance in said gear compensating for the "wasted" gas. But if you get it right... boy oh boy does it feel nice. No automatic can ever be as smooth and efficient - car and driver in perfect harmony - it's what I love about manual transmissions.

So, yes, it hurts the clutch, but probably not as much if you are a) smooth about it and b) relatively quick to engage that lower gear.

I have over 30,000 miles on my 07 Civic sedan - so I will let you guys know if this behavior will cost me a pretty penny later on in the life of the car.
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Old 08-07-2008, 02:36 AM   #3 (permalink)
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I don't think blipping the throttle to rev match consumes that much gas, but I've never actually measured the difference. IMO doing a clutch on a FWD is a pain in the butt, so I'd side on rev matching for long life...
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Old 08-07-2008, 02:40 AM   #4 (permalink)
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Alright thanks, I feel better. I agree about those perfect shifts; I get them from time to time, and it just feels good.
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Old 08-07-2008, 10:22 AM   #5 (permalink)
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There's lots of good about proper shifting. The oldschool doubleclutch is definately the best because you are not only saving your clutch from 4000rpm differentials, you are also saving your syncros frm the same. Personally I "half clutch". I drop a little throttle to remove the load from the engin so i can just slip into neutral without the clutch at all, then i match revs bringing the tranny AND engine up to the correct speed, then tap the clutch to ease the pressure off the tranny while i pop it into gear. Very smooth, no wear on the clutch or the synchros because everything is going the same speed on engagement.

Don't get sucked into the very silly thinking that pressing the pedal is what wears the clutch. It is the engagement at different RPMs.
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Old 08-07-2008, 12:14 PM   #6 (permalink)
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Quote:
Originally Posted by MazdaMatt View Post
Don't get sucked into the very silly thinking that pressing the pedal is what wears the clutch. It is the engagement at different RPMs.
MazdaMatt - very astute observation.
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Old 08-07-2008, 12:16 PM   #7 (permalink)
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I was told the opposite by my mechanic friend! But she is not a good driver of standard OR auto!
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Old 08-07-2008, 12:52 PM   #8 (permalink)
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Speaking of clutches. Just had a new one installed so I thought that would be the end of the shuddering starts. Not so. Unless I am on level ground and very slowly ease the clutch out I still get a bit of the shudders.... WTH.

It definitely shifts from gear to gear better. Does it need adjusting or do I have something loose in the front end causing this?
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Old 08-07-2008, 12:59 PM   #9 (permalink)
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Please take no offense - how long have you been driving standard, and what car are you driving?

When I was new to my Protege5 I was always complaining about how it shuttered on starts. I thought it was the car (naive or what!), but now its quite smooth. I have heard a lot of other protege owners (young people) complain about it too.
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Old 08-07-2008, 02:00 PM   #10 (permalink)
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My Civic does the shudering too when it's cold. It goes away after a few miles of driving. It has 190k miles on it, so I thought it was the age of the clutch showing.


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