Clutchless shifting a manual

[Nayov]

(Before anyone goes crazy, YES I do enjoy shifting a manual and do have automatics in the other cars; this only a question.)

Is it harmful to shift a conventional transmission without the clutch? Assuming of course there is no grinding. It's not a smooth operation unless I suppose you shift at the sweet spot (road and engine speed).

I gather that the big rigs are supposed to be shifted without a clutch, but is that because it would be too onerous given the frequency of shifting and the number of gears, or is there a mechanical reason?

 

[Astro14]

When I had a broken clutch cable, yes, I drove home that way. Precisely rev-matching both the upshifts and the downshifts. Not something I would choose to do, but every manual owner should develop the feel necessary.

 

[bonjo]

same as astro for me with broken clutch cable. rpm/road speed matching is critical and you need to be forceful.

Ok to get you home but damaging on the gears long term.

One problem is the gears cutting angle to reduce gear whine & also the presence of the synchromesh. So keep using the clutch. A bleep on the throttle both going up & down will make the gear chage a lot smoother irrespective of the synchro.

If you have straight cut gears (as I do on my bikes), I prefer clutchless upshift at out of town speeds

 

[SHOZ]

I had a '79 Mustang that would break a small cable that operated the throwout bearing yoke every 40k or so. I learned to shut it off at the stop lights and start in first then shift without clutch the rest of the way home....

 

[fdcg27]

Some cars are really easy to drive sans clutch. Our old Civics and my MGB certainly were.
A tach does help and if you do a good job of matching revs to road speed for the next gear you select, up or down, you get an extremely smooth shift with no mechanical protest at all. It just drops right in and requires no real force on the shifter.

 

[barryh]

Cutchless shifts are easy enough when the gap between ratios is small, therefore I can do it silently on my motorcycle between 4th and 5th and there is no synchro to help either. 3rd to 4th is possible but not so sweet. I wouldn't even attempt the lower ratios unless the clutch cable broke although I have done it that way when there was no choice. Paddling away from the lights is fun then snick into 1st.

I have never tried it in a car but I guess the same principle applies. I can't imagine wat you do at the traffic lights.

If you can do it silently then there is probably no excessive wear taking place. If it goes in with a bang I think the answer is obvious.

 

[tnt_motorsports]

I used to shift my 1991 Mazda B2200 with a 5 speed all the time without the clutch. I put ~300k KMs on it so I don’t think it was a factor. The truck died from other causes not clutch or transmission issues.

Just my $0.02

 

[ElectroMechanoMan]

I had a ‘92 Dodge W250 with a Cummins engine and a Getrag 5 speed. That transmission was the best shifting I ever drove, with or without a clutch. Speed matching was by feel. A small tap on the throttle would assist grabbing the next gear. It was very smooth either up or down shifting.

 

[fdcg27]

I also recall some miles in a '65 GMC 3/4 ton 4X4 four speed V-6 that was dead easy to shift without the clutch.
It was also a remarkably comfortable truck for what it was and was a bit of a bear otherwise lacking both PS and PB.

 

[ARCOgraphite]

same as astro for me with broken clutch cable. rpm/road speed matching is critical and you need to be forceful.

Ok to get you home but damaging on the gears long term.

One problem is the gears cutting angle to reduce gear whine & also the presence of the synchromesh. So keep using the clutch. A bleep on the throttle both going up & down will make the gear chage a lot smoother irrespective of the synchro.

If you have straight cut gears (as I do on my bikes), I prefer clutchless upshift at out of town speeds

Just for general information purposes for who may not know.

With modern automotive constant-mesh transmissions (most all of them) you do not actually "shift gears" the forward gears are all in position and meshed - but all are "floating" and idling - except for the one selected.

Rather, you are locking a floating gear to the output shaft by "forcing" a channeled collar over dogs at the leading edge of the gear - then the gear will be locked to the output shaft and transfer torque

Conversely, the HD Eaton Road Ranger is not a synchronized transmission

 

[ecotourist]

I had a '79 Mustang that would break a small cable that operated the throwout bearing yoke every 40k or so. I learned to shut it off at the stop lights and start in first then shift without clutch the rest of the way home....

My '65 Comet had a mechanical clutch linkage that came apart one day. I too started it in first gear and then shifted without the clutch to get it home. Stopped at all the stop signs too by shutting off the engine and starting it in first gear again.

I wouldn't like to have to do that very often.

 

[dfarr67]

Never had the need nor the guts to try.

 

[Elkins45]

When I had a broken clutch cable, yes, I drove home that way. Precisely rev-matching both the upshifts and the downshifts. Not something I would choose to do, but every manual owner should develop the feel necessary.

What do you do at red lights?

 

[weasley]

What do you do at red lights?

The best approach is to anticipate them and approach slowly, hoping they will change before you each them - maybe even slip it into neutral on the approach then select the best gear when they change. In a bind you can start the engine with the car in gear and it should bump to life.

 

[JHZR2]

I had a '79 Mustang that would break a small cable that operated the throwout bearing yoke every 40k or so. I learned to shut it off at the stop lights and start in first then shift without clutch the rest of the way home....

That sounds horrible. I can see how/why it’s necessary, but I’d cringe trying to get the car started like that at stoplights.

 

[Astro14]

What do you do at red lights?

Slow down way early and crawl up to them, so that they change before you get there. Worst case, shut the engine off, restart (with the clutch pedal to the floor, to satisfy the safety interlock) in first when it turned green.

 

[SHOZ]

That sounds horrible. I can see how/why it’s necessary, but I’d cringe trying to get the car started like that at stoplights.

You had to be on your toes and make sure nothing was in front of you. What else you going to do?

 

[Chris142]

The only the I use the clutch is to start and stop. Jeep is nearing 200k. Does it hurt anything? Not that I have seen.

 

[barryh]

Clutch cable failure only happened to me once in 1972 when riding my motorcycle home from work in heavy traffic. I must have had 10 or 12 sets of Red lights to go through. The bike was a little Ducati Monza junior and relatively light weight, so easy to paddle and then snick it into first at walking speed. Even starting off that way and the subsequent clutchless changes could not have been good for the gearbox and some months later the gearbox selector mechanism did fail. Who knows if the two things were related.

 

[supton]

Had a pressure plate let go and could not clutch the motor. IIRC I would take off in 2nd and shift to 4th or 5th? I was still something of a newb at driving, and I think I was reluctant to go beyond that. Had to drive 50 miles to get home, want to say, thankfully it was a handful of lights/stops (had dad find a back way). Later in college I got more adventurous and tried it out on a Subie, was almost ok at it. Fun skill to have.