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post #1 of (permalink) Old 07-20-2004, 03:55 PM Thread Starter
 
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T5 clutchless shifting

Don't ask me what possesed me to try this, but I have found that I can start from a stop in first, then make the next 3 shifts without using the clutch. It slips into gear without resistance, clunk or noise if I have the rpms at what they should. Anyone else try this? Is something wrong or right here?
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post #2 of (permalink) Old 07-20-2004, 04:34 PM
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Re: T5 clutchless shifting

[img]images/graemlins/grin.gif[/img] Drive a stick enough and you know at what engine rpm vs. vehicle speed the next gear will slide in at, going up and coming down. In fact you can over drive a gear(long shifting as opposed to short shifting?) then skip a gear or two or three or four. As my wife says, "You wanna see my famous first to fouth shift?" Don't worry hon, I'll catch the rod when it comes flying out the side of the engine. You only need the clutch to start. When you are coming to a stop let it coast a little and slip her in the big "N" position.
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post #3 of (permalink) Old 07-20-2004, 04:43 PM Thread Starter
 
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Re: T5 clutchless shifting

What's keeping the input end of the transmission spinning aside from intertia of the internal parts? If it's just inertia, does that mean I have to shift before it slows down?
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post #4 of (permalink) Old 07-20-2004, 05:37 PM
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Re: T5 clutchless shifting

The transmission input shaft is spinning at crankshaft speed because it's connected through the (engaged) clutch to the crankshaft. You have to time your shifts so that the engine, and the transmission input shaft, have slowed down to the right speed to match the rest of the transmission in the next gear.

Normally, with the clutch disengaged, the synchronizer slows (or speeds up) the input shaft to match the speed of the next gear as you select it, and blocks engagement until the speeds are matched. The fact that you can do your clutchless shifting easily suggests that the synchronizers are somewhat worn. Usually, if the speeds aren't exactly right when you first try the shift, the snychros will block the shift, and then keep it blocked, even when the speeds are made right.

Talking there about synchronizers in general. The T5 may behave differently.

Motorcycle transmissions do not have synchronizers. The parts are light weight, and the ratios are close together. That allows you to pop from one gear to the next with only a brief decrease in power to take the pressure off the gears and allow them to disengage. Same with race car transmissions.


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post #5 of (permalink) Old 07-20-2004, 05:51 PM Thread Starter
 
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Re: T5 clutchless shifting

Thanks for the explanation. I confess I've never looked closely at the innerds of a manual tranny to see how those synchonizers work.

Any harm in doing what I am doing? Is it harder on the synchro's or anything? It's kinda fun. I wouldn't do it if it made a grinding or popping into gear. I'm just surprised how easy it is to do. I expected to hear grrrrrrrrr as I attempt to engage the next gear.
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post #6 of (permalink) Old 07-20-2004, 05:57 PM
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Re: T5 clutchless shifting

No harm done IF the speeds are exactly matched when you engage the gear. If there is any mismatch, the synchro will try to correct it, which will require that it change the speed of the entire engine. Since synchronizers are basically little clutches, that obviously causes a lot of wear on them.
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post #7 of (permalink) Old 07-20-2004, 09:26 PM
 
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Re: T5 clutchless shifting

i shifted my t-4 without the clutch. It had bad syncros so that was the only way i could shift quickly, without it grinding. Now i just put in a good t5 so i shift normally, i found it to be kind of hard to shift clutch-less without a tachometer.
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post #8 of (permalink) Old 07-21-2004, 12:02 AM
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Re: T5 clutchless shifting

[img]images/graemlins/grin.gif[/img] I would never do such a thing [img]images/graemlins/grin.gif[/img]

I had a 1966 Belaire, 283 with a column shift... nevermind..

T5's get so much crap. [img]images/graemlins/frown.gif[/img]

Dale
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post #9 of (permalink) Old 07-21-2004, 08:40 AM
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Re: T5 clutchless shifting

Well Tim...after 22 yrs of running longhaul in a big truck...let me tell ya...any tranny can be shifted without a clutch...just a matter of listening to the engine and knowing where to shift..I ran a truck that had a 5 speed main box..and a 5 speed brownie box...thats a total of 25 forward gears...lol..and all you have to do is listen..and learn to feather the stick into the slot..they'll drop right in without a hitch...it's really pretty easy to do if you know the engine rpm sound and the tranny..

[img]images/graemlins/givemebeer.gif[/img]
post #10 of (permalink) Old 07-22-2004, 09:50 AM
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Re: T5 clutchless shifting

many a time have i gotten home with no clutch, in my jeep and my car (59 ford fairlane). good thing to know about.
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