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No clutch trans shift

Hello everyone;

The question that I have has intrigued me for years, but I just keep forgetting to ask it (sound familiar?). Is there any harm that is caused by disengaging the transmission from being in gear to neutral without incorporating/depressing the clutch? Thanks to all of you manual trans experts for your wealth of knowledge on this one.

Old 544

If done properly, it won’t hurt it. If done improperly, it certainly can. Same with shifting without using the clutch. I suggest erring on the safe side.

Placing a manual transmission from any gear into neutral without stepping on the clutch puts undue wear on the synchros. Not something you want to make a practice of doing.

Tester

I’m with Mark on this. It needs to be done when no load is place on
the transmission. And that requires careful throttle modulation. The shifter would slip out of gear without any friction.

When done wrong, it places wear on the shift forks and dog teeth. if that happens often enough, the shifter would pop out of gear by itself.

It can be done without causing harm, but if not done correctly, it will cause harm. When coasting to a stop or lower speeds, I can very easily shift to neutral in my car at 11 mph from second, 16 from third, 24 from fourth, and 32 from fifth. Those speeds work in my car. I do that with some frequency.

Disengaging a gear from a higher speed can be done, but I see no need for it. I’d rather wear out and replace some clutch parts than risk damaging internal transmission parts.

The gear (actually the synchronizer) needs to be disengaged while there’s no load. The easiest way to remove the load is by pressing the clutch pedal. You can also wait until the car has slowed to a speed at which the engine is at idle speed. The other way is to shift to neutral at just the right time while releasing the accelerator. It has to be done when the engine isn’t trying to make the car go faster, and when the motion of the car isn’t trying to make the engine go faster. It takes practice, but I see no reason to do it.

Agree with the posts thus far. Think of it this way. If you want to train, or teach, your transmission how to pop out of gear into neutral all by itself; then this is the way to do it.

I know how to shift without using the clutch, I’ve done it, and I don’t do it because I’d rather my transmission stay in the gear I put it in.

As stated above, if there is no load on the trans, then it will be OK. Else it will wear the shift forks.

I don’t see where the wear on the synchros occur when coming out of a gear w/o depressing the clutch. Slippage of a synchro on a gear’s collar occurs when going into a gear - which is a very different question.

so as I understand it, the shift forks are moving the lay shafts to disengage the gears. but how can excessive wear and tear occur if everything is moving in a synchronous fashion (i.e no load situation, and we are talking decel only to go from 3rd,4th,5th to neutral) and sufficient lubrication is present? it seems that by eliminating the clutch assembly from being used that fewer components are at play overall.

It is really all about technique. One driver could do it properly for many years with no problems. Another might do damage due to poor technique. Say someone isn’t good at working the gas petal to get to the no load state and the trans starts to slip out but 1/2 way to release the load on the trans increases (too much or too little gas given by driver) then the transmission “snaps” out of gear as a result. Enough poor technique snapping and it starts popping out of gear on its own.

If a driver states he has been doing the slip out of gear for years on multiple car with no problems I believe him. If another says he did it and his transmission started popping out of gear I believe him too. The car I did the most often was a '71 VW camper bus. The motor had so little power it was just super easy to do. It was also a very easy transmission to shift “clutchless” which was a good skill to have since the clutch cable tended to break on these cars every couple of years. I could do clutchless shifting on my '67 Mustang (V8) but it took a much greater degree of “touch” to get it right. The additional power was harder to control as far as maintaining that important “no load” state.

The shafts just spin; they aren’t moved around by the shift forks. Gears just rides on the output shaft and aren’t engaged to it until a sleeve, which is moved by a shift fork, slides toward one of the gears and locks it to the output shaft.

Unlike the gears, the sleeves aren’t dipped in oil as oil causes unnecessary drag. Shift forks getting drops of oil flung toward them by the gears have no problem moving the sleeves around to engage gears so long as they aren’t forced. This is why you don’t rest your hand on the stick and you don’t shift it into neutral without using your clutch.

Many truckers have the skills to shift out and into the next gear without touching the clutch. Unless you have the shifting skill that they have, don’t do it.

old 544, an EXPERT driver can shift a manual transmission into 2ed on up or down without causing any damage. It just takes some skill and practice to exactly match engine speed to road speed so there is no load on the transmission when these clutchless shifts are made…

Slipping a manual transmission into neutral without clutching and without damage is fairly easy once the technique is mastered. Little pressure on the gear-shift is required…But Why?

Back in the days of the Borg Warner automatic overdrive, one could shift without the clutch if the overdrive was engaged. The car had free wheeling and clutchless shifting after starting off was possible.
Also, Packard had an electric clutch which allowed for clutchless shifts and Hudson had its “Drivemaster” which operated the clutch. I believe the 1931 or 1932 Buick had a vacuum feature to operate the clutch. This all seems like a lot of mechanical complexity to not have to use the clutch.

Brings to mind the Chrysler “Fluid Drive” which used a fluid coupling… You could just put them in 2ed gear and drive around town all day without shifting if you wanted…

@Caddyman-I remember these transmissions well. I owned a 1948 Dodge with the fluid coupling. The coupling was between the flywheel and the clutch. It would allow high gear starts, but was painfully slow. However, it did not let one shift without the clutch. There was a semi-automatic box that was offered in the Chrysler, DeSoto and Dodge lines that had the fluid coupling and the clutch. However, the transmission had two ranges and two speeds in each range. Normal driving was done in the higher range. One would accelerate up to 15 or 20 mph and then release the accelerator and the transmission would shift.
Plymouth had a different arrangement in 1953 and early 1954. The optional Hy-Drive had a torque converter, clutch and 3 speed transmission. One could drive the car in high gear and the torque converter supplied the torque multiplication for better acceleration from a dead stop. The torque converter and the engine shared the same oil which really led to problems.

I don’t know. I have owned and driven manual transmission cars for many years and have not done what you suggest for enough miles and years to know if this is harmful for a transmission.

Shifting into neutral at the instant you take your foot off of the gas allows you to do it with no load on the forks or gears. In fact, it is very difficult to move from any gear to neutrual when the tranny is under load. I do not suggest shifting into any other gear, even though it is physically possible to match RPMs and make it work, but neutral is no problem.

MG throwout bearings are made of graphite, like a 3" ring of “lead” from a pencil. Replacing one requires removing the ENGINE. Not a job you want to do very often. That being the case, I’ve shifted my MGs into neutral that way for 45 years. Never had a transmission issue. For the same reason, I also ALWAYS sit at traffic lights in neutral, but that’s another discussion that has been hashed out here before.

Thanks to everyone for the comments. Shifting to neutral without clutch application during no load is an easy proposition in my vehicles, no less strain that when depressing the clutch. However, any other time is virtually impossible without tremendous effort, and it is a practice that I avoid.

MG McAnick reminded of a gentleman that I knew years ago who specialized in British cars. The trick I learned from him to easy clutch replacement on an MG was to cut out the crossmember, and then weld it back in. He could replace a clutch assembly in about 4 hours. Talk about beating the book on flat rate!!!

The part that would concern me would be excess wear on the shift fork and synchronizer sleeve. Due to non-use of the clutch some extra pressure would need to be applied to slide it out of gear and possibly cause a problem.

Some cars may be more prone to this than others and Subaru is one of the prone ones. The shift forks have to be centered in the sleeves and if .010 of an inch or whatever gets scrubbed off of the fork, sleeve, or both then the car owner is left with a transmission that will jump out of gear.
(I’ve done a number of these repairs but in most cases it was due to someone driving around with their hand resting on the gearshift lever. That created just enough movement off of the shift rail detent to cause wear on the parts I mentioned.)

On a random basis I don’t see nudging it into neutral as being a problem but I sure wouldn’t make a habit of it.