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Old 11-15-2021, 09:34 AM   #61 (permalink)
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It is of course difficult to turn the car around with the engine off so I rarely do that (it involves a handbrake turn in my driveway).
I can do it! My driveway is slightly downhill from the road. I coast in, quickly turn back into the road, and then coast backwards into the driveway.

I've made u-turns on hills with the engine off too!

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Old 11-15-2021, 10:05 AM   #62 (permalink)
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. Of course if you can perfectly match revs every time, there won't be any wear. Rev matching with the clutch would be the best. My Insight demands this to downshift into 1st or 2nd gear. It'll growl at me if I don't!
Disengaging the clutch removes the engine speed from the gear. The idea is to match engine speed to the gear set. My schoolbus had an input shaft brake for shifts which is why you double clutched it between gears and stomped the pedal to the floor every time
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Old 11-15-2021, 10:16 AM   #63 (permalink)
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Disengaging the clutch removes the engine speed from the gear. The idea is to match engine speed to the gear set. My schoolbus had an input shaft brake for shifts which is why you double clutched it between gears and stomped the pedal to the floor every time
Thanks, I forgot to mention double-clutching! I'm so used to it that I don't even think about it.
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Old 11-15-2021, 04:00 PM   #64 (permalink)
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Originally Posted by Piotrsko View Post
Disengaging the clutch removes the engine speed from the gear. The idea is to match engine speed to the gear set. My schoolbus had an input shaft brake for shifts which is why you double clutched it between gears and stomped the pedal to the floor every time
I also double clutched my school bus. Apparently I was the only one who knew how to do it, since everyone else just pushed on the shifter and waited a good 3 or 4 seconds for the synchros to do the job. I'd get comments on how I could race in a bus professionally if I wanted to.

In my cars I usually would double clutch the downshifts as the upshifts didn't seem to help that much.
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Old 11-15-2021, 04:15 PM   #65 (permalink)
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I also double clutched my school bus. Apparently I was the only one who knew how to do it, since everyone else just pushed on the shifter and waited a good 3 or 4 seconds for the synchros to do the job. I'd get comments on how I could race in a bus professionally if I wanted to.

In my cars I usually would double clutch the downshifts as the upshifts didn't seem to help that much.
It seems to be easier for the synchros to bring the clutch/input shaft RPM down than up. When double clutch downshifting or revving to get back into gear, it seems like slightly overshooting the RPM and letting the synchros bring it down a little works better than slightly underrevving and forcing the synchros to bring the clutch/input shaft RPM up.

If I had to guess why, I'd say because the synchros have friction and oil drag on their side bringing the RPM down while they are fighting friction and oil drag to bring RPM up.

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Old 11-16-2021, 02:54 AM   #66 (permalink)
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Originally Posted by Gasoline Fumes View Post
I can do it! My driveway is slightly downhill from the road. I coast in, quickly turn back into the road, and then coast backwards into the driveway.
Whilst I can do it I find it is not popular with my passengers and it makes a mess of the driveway so it is not something I do often.
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Old 11-16-2021, 07:49 PM   #67 (permalink)
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I'm in E TN which is pretty darned hilly, clutch out and into gear for P&G and have since I bought the truck...in 1987. We were pretty broke for a long time so I drove the truck like gas was way more expensive than it really was. I was P&G before I even knew it had a name.

Teaching the last kid to drive stick finally cooked the first clutch at over 200,000 miles, but the rest of the tranny sounds fine. I might need to replace a bushing in the shifter but the box itself feels as good as it ever did.

Above about 40mph or so, reengaging in top gear, I'll give the gas a quick stab if the engine is running but it's 50/50 on a long downhill I turned it off, so there's nothing to stab. Clutch, gear, let 'er rip.
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Old 11-20-2021, 10:00 PM   #68 (permalink)
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I accidentally tried engine off coasting earlier today (my knee hit the key and shut it off while I was coasting down hill at ~50 MPH). I tried to start it by shifting back into 5th gear which worked perfectly fine with no grinding. Not sure how it went into 5th gear perfectly from 0 RPM but kicked me out that time I tried to shift back into gear from idle. Could a bad/worn synchro work only intermittently?
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Old 11-20-2021, 10:28 PM   #69 (permalink)
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Originally Posted by EcoCivic View Post
I accidentally tried engine off coasting earlier today (my knee hit the key and shut it off while I was coasting down hill at ~50 MPH). I tried to start it by shifting back into 5th gear which worked perfectly fine with no grinding. Not sure how it went into 5th gear perfectly from 0 RPM but kicked me out that time I tried to shift back into gear from idle. Could a bad/worn synchro work only intermittently?
What's the weather been like? I've noticed that if the transmission is cold it can be harder to get things to mesh right in some cars. It might be the other way around in others. If one day it was cold and another hot, maybe that's the reason. Or if you had driven around long enough to warm it up that one time.
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Old 11-20-2021, 11:51 PM   #70 (permalink)
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What's the weather been like? I've noticed that if the transmission is cold it can be harder to get things to mesh right in some cars. It might be the other way around in others. If one day it was cold and another hot, maybe that's the reason. Or if you had driven around long enough to warm it up that one time.
Great point, I didn't think of trans temp. That could be it. One of the gauges I installed is monitoring trans temp, so I'll keep an eye on it and see if I notice any patterns.

It seems like in normal driving the transmission oil temp eventually stabilizes at around 50 degrees over outside temp, but it takes quite a while to get there.

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