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Manual Downshifting question

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Old 10-16-2006 | 05:45 PM
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Manual Downshifting question

K this is my first manual so be nice.

When doing say 60MPH in 5th gear when I downshift to 3rd, it is very difficult. Its almost like I have to force it. But if I double clutch its easier. Also downshifting from 5-->4-->3 is also easy.

So my question is. Is it normal to experience some resistance when downshifting at high speeds while skipping gears?

Also I wasn't sure if that TSB (clutch hard to disengage) is related to my problem,

I will be changing my tranny fluid soon and will have the dealer do the TSB when they do it. But just wanted to know if what I am experiencing is normal and also if it is a big NO NO to skip gears

thanx

Last edited by Unhooked; 10-16-2006 at 11:04 PM.
Old 10-16-2006 | 05:52 PM
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Are you rev matching when downshifting from 5th to 3rd?
Old 10-16-2006 | 07:13 PM
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^ yea cause if you are not, then you are really stressing the car...
Old 10-16-2006 | 10:45 PM
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Not too sure if rev matching comes into play here. I usually rev up before letting go of the clutch...bt that is not the issue. The issue is the stick will not go easily into the 3rd gear position when trying to do a 5th to 3rd shift when doing 60MPH. But when I get it in 3rd I rev up and let go of the clutch.

Unless I have to rev in neutral and keep the revs up before shifting stick position to 3rd gear I don't know what I am doing wrong

Last edited by Unhooked; 10-16-2006 at 11:03 PM.
Old 10-16-2006 | 11:09 PM
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That's right. If you're in 5th and just shove it into 3rd it won't go in easily.

But if you double clutch and rev match properly, it will slide right in.

Let me recommend one of my favorite books. A bit old, dated for actual performance driving, but excellent if you'd like some basics to apply to spirited driving on the street. "The Technique of Motor Racing," by Piero Taruffi. (Published in the late 50s, and still in print.) The "Silver Fox" was a race driver from the 1920s through the 1950s. Doctorate of Engineering, Grand prix winner and winner in the Targa Florio and Mille Miglia. He gives a blow-by-blow, by the numbers, description of downshifting via "double declutching."

If you google - or even just search this site - you'll find good descriptions of downshifting and double-clutching, but IMHO none better than Taruffi's.

Ken

Last edited by ken-x8; 10-17-2006 at 01:02 AM.
Old 10-17-2006 | 12:09 AM
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Originally Posted by Unhooked
Not too sure if rev matching comes into play here. I usually rev up before letting go of the clutch...bt that is not the issue. The issue is the stick will not go easily into the 3rd gear position when trying to do a 5th to 3rd shift when doing 60MPH. But when I get it in 3rd I rev up and let go of the clutch.

Unless I have to rev in neutral and keep the revs up before shifting stick position to 3rd gear I don't know what I am doing wrong
If you're holding the clutch down, revving up to 6000 RPMs, sliding it into 3rd and then letting the clutch out then it should be fine. If there's still resistance, then obviously there's something up with your transmission. You could try changing your tranny oil if you don't think it's a mechanical problem.
Old 10-17-2006 | 12:49 AM
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Is double clutching really that necessary now with the modern gear synchronizing? I have never had a problem skipping a gear while downshifting if I rev properly.
Old 10-17-2006 | 12:53 AM
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its one of those believe in god things. it might not help but it cant hurt.


as i see it(the double clutching that is)
Old 10-17-2006 | 01:00 AM
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There was a huge thread about double clutching a month or two back, it wouldn't be hard to find. But yeah, like mac said.
Old 10-17-2006 | 01:02 AM
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It's not necessary, but it's much easier on the transmission. I've never had a car where I could just push it into a lower gear without a fair amount of resistance. You won't grind the gears, but it puts wear on the synchros and if you habitually push hard there's a chance of bending the shift forks.

Revving to match speed when you let the clutch back out has nothing to do with how easy it is to get into the lower gear.

Double clutching downshifts is fun. Doing it with heel and toe while braking is even more fun.

Ken
Old 10-17-2006 | 01:28 AM
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[clutch in->neutral->clutch out->blip throttle->clutch in->gear in->clutch out]

Best way to downshift imo
Old 10-17-2006 | 01:35 AM
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^rev matching has nothing to do with the ease on the gearbox, yes, but simply pressing the clutch and shifting into lower gear and then letting the clutch out as if you were up-shifting will take some effort, and you might have to crunch it into gear, just like you said in your first post. Double clutching might the help the easiness but I've also found that holding the clutch down for a few seconds works just as fine. Sometimes I find myself double clutching as well, depending on what I'm doing. Transmissions vary.

Spirited driving is hard to put in words, a lot of it is just intuitive now after reading, trying it out, trial and error, etc.
Old 10-17-2006 | 09:09 AM
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Hmm thanx for all the suggestions guys..this is what I have discovered so far

If I am in 5th, I clutch in shift to neutral, shift to 3rd while revving and clutch in, the lever moves easily, I then keep the revs up and let go the clutch and all is good.

Raptor - you are correct about the effort part it takes to crunch it into a lower gear. That is what I am experiencing and hence the thread. I am going to try and hold the clutch for a few seconds and then will shift into 3rd.

SOmeone told me that I have to rev to get the synchros ready to go into the the lower gear.
Old 10-17-2006 | 09:14 AM
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Without proper revmatching when downshifting, you either wear out the synchro faster or the clutch faster.
Old 10-17-2006 | 10:16 AM
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Originally Posted by tiltmode43
[clutch in->neutral->clutch out->blip throttle->clutch in->gear in->clutch out]

Best way to downshift imo
Just do this for now. Rev to about 6500 so that when you let the clutch out after you shift into 3rd, the revs will fall around 6000.
Old 10-17-2006 | 11:10 AM
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Another factor to consider is the temperature of the transmission. A well warmed up tranny shifts a bit easier than a cold one.

1.3L
Old 10-17-2006 | 11:19 AM
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Personally, I don't even bother downshifting into 3rd unless I'm 55 or slower. at 60 I'd go into 4th first...

Is it just at 60 that you have issue, or does it go into 3rd from 6th at 50 mph fine?
Old 10-17-2006 | 12:32 PM
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haven't tried that yet...I usually downshift to 4th but knowing that 3rd gear before redline is about 80-85 MPH, I thought I'd try it. Going into 4th too takes a lil effort but not as much as it takes from 5th to 3rd
Old 10-17-2006 | 12:37 PM
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Originally Posted by mysql101
Personally, I don't even bother downshifting into 3rd unless I'm 55 or slower. at 60 I'd go into 4th first...

Is it just at 60 that you have issue, or does it go into 3rd from 6th at 50 mph fine?
Some of us don't have FI and need all the power we can get =P.

I downshift into 2nd if I'm going 50-55.
Old 10-17-2006 | 09:39 PM
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last second thought....synchos are taking a pounding when u do this.

clutch in, neutral, rev to match, into gear, engage clutch. win-win.

as far as i've heard, the 8 seems to have some good ones though, might even be double or triple syncros with their known durability.

...Ford could certainly take some notes on this one. Their T-45...ugh.
Old 10-20-2006 | 02:16 PM
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I agree the engine takes a beating, so always rev match, and never down shift when coming to a stop, That said, I have never have a problem shifting from any gear to any other. I routinely shift from 6th to 3rd or 5th to third, and never have a problem with the shift itself (with the clutch in, I don't think the transmission has any idea how fast the engine is going. In fact, I can shift from 1st to 6th and back again sitting in my driveway with the emergency brake on.
Old 10-20-2006 | 02:29 PM
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Originally Posted by fredw1
I agree the engine takes a beating, so always rev match, and never down shift when coming to a stop, That said, I have never have a problem shifting from any gear to any other. I routinely shift from 6th to 3rd or 5th to third, and never have a problem with the shift itself (with the clutch in, I don't think the transmission has any idea how fast the engine is going. In fact, I can shift from 1st to 6th and back again sitting in my driveway with the emergency brake on.
I'm not responsible for any damage caused, but if you want to test your theory out, go 70 mph in 6th, then shift into first (clutch all the way in) and see what happens.
Old 10-20-2006 | 02:56 PM
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Heel/Toe Downshift, damn you!
Old 10-20-2006 | 03:09 PM
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Is there a requirement to using heal and toe? A really small foot maybe? Because I find it hard to do it with my 10 1/2-sized running shoes.
Old 10-20-2006 | 03:21 PM
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Originally Posted by mysql101
I'm not responsible for any damage caused, but if you want to test your theory out, go 70 mph in 6th, then shift into first (clutch all the way in) and see what happens.
i'll second that . And take a video of it to show us all - can't wait !!!!


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