Manual transmission poll

[280plus]

D

Is this a question?

Rhetorical mostly that I followed with the answer I like best. "slipping" the clutch is the correct terminology. All those other manipulations, to me anyways, are just extra steps that are unnecessary once you get the hang of "slipping" the clutch and holding the car with it momentarily while shifting your foot from brake to gas. I drove a clutch from about age 16 to maybe 40 until I got tired of aall the clutch work involved with being in bumper to bumper traffic here in CT.

I never really understood "double clutching" exactly though if someone wants to tackle that one. I know what I THINK it is but I'm not sure I'm correct.

[K Frame]

Double clutching is pretty much a thing of the past because most cars and trucks now have synchronizers on their transmissions.

To do so, you push the clutch in, take it out of gear, release the clutch, push it in again, and then go into the next gear.

The synchro failed on my Dad's International Disaster and that's how we had to shift the last year or so he had it.

[Tallpine]

Rhetorical mostly that I followed with the answer I like best. "slipping" the clutch is the correct terminology. All those other manipulations, to me anyways, are just extra steps that are unnecessary once you get the hang of "slipping" the clutch and holding the car with it momentarily while shifting your foot from brake to gas. I drove a clutch from about age 16 to maybe 40 until I got tired of aall the clutch work involved with being in bumper to bumper traffic here in CT.

I never really understood "double clutching" exactly though if someone wants to tackle that one. I know what I THINK it is but I'm not sure I'm correct.

Well, some vehicles won't even start on level ground without some gas pedal, let alone hold on a hill. 


Double clutching is used mostly on trucks.  Even when not absolutely necessary, it does take a lot of load off the synchros especially when downshifting.  The idea is getting everything going the same speed in the gear box before shifting into gear.  It's actually easier on the clutch even though it seems like you are working it twice as much.

Also when downshifting, if you rev up the engine just right before or as you let out the clutch, you don't get that sudden lurch.  Even if you are using the gears to slow down, it still makes it smoother.  You just back off the gas pedal once everything is in gear and rolling smoothly.

To really appreciate that sort of thing, you have to drive an old 2-ton or bigger truck over a Colorado mountain pass with a heavy load.    Bonus points if the brakes ain't too good 

[Chester32141]

Long as we're about it let's touch on the whether harmonic distortion is what allows shifting w/o the clutch to be done smoothly ... 

[slingshot]

I prefer a standard transmission.  I park my little Toyota in 1st gear always.  I seldom turn the wheels toward a curb if one exists unless I am on a steep grade. 

A while back, my truck was parked in my driveway in 1st gear (slight grade).  I looked outside and my truck had drifted across the street into the neighbor's yard.  I ran outside and it had slipped out of gear.  Now I ALWAYS park that truck in gear and with the emergency brake ON.  That is my advice.  I would not disable anything.

[280plus]

Well, some vehicles won't even start on level ground without some gas pedal, let alone hold on a hill.  You're not starting without gas, just holding it there for that split second while you release the brake and give it some gas. I don't know about heavy trucks but a car should be able to be held on a hill without brakes by slipping the clutch. At least all mine were.


Double clutching is used mostly on trucks.  Even when not absolutely necessary, it does take a lot of load off the synchros especially when downshifting.  The idea is getting everything going the same speed in the gear box before shifting into gear.  It's actually easier on the clutch even though it seems like you are working it twice as much. I remember that now. I had a totally different thing in mind. Release the clutch, let the motor idle down, re-engage the clutch and this will slow the car down without downshifting.

Also when downshifting, if you rev up the engine just right before or as you let out the clutch, you don't get that sudden lurch.  Even if you are using the gears to slow down, it still makes it smoother.  You just back off the gas pedal once everything is in gear and rolling smoothly. I recall if you get the tranny spinning at the right speed between shifts you can shift without the clutch. "power shifting". Good way to blow the tranny if you're not so good at it.

To really appreciate that sort of thing, you have to drive an old 2-ton or bigger truck over a Colorado mountain pass with a heavy load.    Bonus points if the brakes ain't too good   You're a braver man than I ! :D

[Tallpine]

You're a braver man than I

The brakes on those old trucks weren't so great even if everything was working properly.  They really were intended for farm use instead of steep mountain roads.  I had to use 2nd gear all the way up and down the steepest parts (about 8 miles on each side).  If you tried to catch 3rd gear going down, well - you were going to die at the next switchback.

I don't know about heavy trucks but a car should be able to be held on a hill without brakes by slipping the clutch. At least all mine were.

I've only owned three cars in my life and the only one that was a manual was the VW that I married into.

A real truck usually has a lower gear that makes it easy to start on a hill, but you can't go very fast until you can shift.

I'm still not used to these "newer" pickups with five speeds.  I'm not sure that first is even as low as second in my old 4 speed GMC    You can start it on level ground in third with a little finesse. 

A five speed truck/bus you only use 2-5 in normal driving.  First is like low range.

If you are good with a clutch, you can get out of a ditch or slippery spot by starting in the next gear up from what you usually do.  Pull the engine down to just about to die and the wheels don't spin.

[280plus]

My first standard was a 351C mustang with a Hurst shifter. It locked out each gear as you shifted out of it so all you had to do was yank it back and forth and it would shift from 2nd to 3rd without having to push it sideways. Took me about two weeks to figure this out before I stopped trying to start in 3rd gear. You had to force it to the left to defeat the lockout mechanism to get it back into 1st. By slipping the hell out of the clutch I would get it to start in 3rd wondering why it was so hard to get it going, cussing the car out the whole time. I thought the car was effed up, but it was only me.

 

[Hawkmoon]

Long as we're about it let's touch on the whether harmonic distortion is what allows shifting w/o the clutch to be done smoothly ... 

Answer: No.

Anyone who understands what double-clutching is and why it works can drive a manual transmission without using the clutch. It's exactly the same principle -- get the parts on both ends spinning at the same rotational speed so they can come together non-destructively.

[Tallpine]

Answer: No.

Anyone who understands what double-clutching is and why it works can drive a manual transmission without using the clutch. It's exactly the same principle -- get the parts on both ends spinning at the same rotational speed so they can come together non-destructively.

The few times that I tried it, I had more trouble getting out of gear than getting into the other one.  Not sure how it would ever work growling up a steep hill.

If you get double clutching just right, the transmission will actually pull itself into gear as you let out the clutch.  Hard to explain ... just barely towards the new gear from neutral and start letting the clutch out, and the transmission pulls the lever right out of your hand and into gear.

[Fly320s]

I prefer a standard transmission. 

So, you like automatic transmissions?  Those are standard equipment theses days.   

[K Frame]

My friend Dave has a beautiful 1971 Corvette.

A few years ago when I was out I shocked the hell out of him by shifting up and down through the gears with no effort without using the clutch.

2,500 RPM is the magic number for that car.

I used to do it with my old Outback, but I've not really tried it with the new Outback.

[AmbulanceDriver]

My friend Dave has a beautiful 1971 Corvette.

A few years ago when I was out I shocked the hell out of him by shifting up and down through the gears with no effort without using the clutch.

2,500 RPM is the magic number for that car.

I used to do it with my old Outback, but I've not really tried it with the new Outback.

First time I saw my Dad do that, I was  ...   

So I made him teach me how he did it... 

The transmission on my '96 Camry was incredibly easy to do this with, especially from 3rd to 4th, and 4th to 5th.  1st to 2nd was the toughest.   

Always weirded out my friends when they saw me do it...

[K Frame]

First to second is normally the toughest with any car, and second to first? 

[Gewehr98]

So Ford and GM are collaborating on 9 and 10-speed transmissions now.

The new Jeep Grand Cherokee gets an 8-speed automatic.

You'd think driving one of those would be a cacophany of hunting for gears, vs. an honest-to-gawd CVT.

I guess they can't build a CVT that handles any more horsepower than a Nissan Murano?

[ArfinGreebly]

In 1986 I went to Los Angeles to work on a [mumble] project that never funded.  I was down there for some three or so months.

While I was down there, the clutch cable on my Karmann Ghia gave out, and I suddenly had no functioning clutch.  At all.  And, because said project hadn't funded, there was no dough to get it fixed.

For the next six or eight weeks I used that "crash shift" trick my mechanic taught me -- basically double-clutch without the clutch -- and managed to drive in traffic, stop at lights, and navigate all over the place.  Got really good at parking in places that would let me do a forward-only startup.

Starting from a light was tricky, and relied on a good starter motor and decently tuned engine.  Turn off engine.  Shift into 1st gear.  Turn the key.  Car fires up, then work through the gears to stay with the traffic.  (The stomach knot that goes with this was incentive to learn how to drive in traffic without ever actually coming to a complete stop.)

It only takes a few "grinder moments" to act as a learning aid for proper "tone" from the engine (no tach, so you had to use your ears).

When I got back to Vegas, the first thing I did was visit my mechanic.  Told him what I'd been up to, thanked him for teaching me clutchless survival.  Big grin.  He replaced the clutch cable at no charge.

[280plus]

^^^ been there. Hydraulic clutch failed just before my bi weekly trip from Hartford to Trenton to see the GF. No way was I missing that. Both ways, no clutch driving just as you describe. Oh to be young and foolish again. 

[Chester32141]

Answer: No.

Anyone who understands what double-clutching is and why it works can drive a manual transmission without using the clutch. It's exactly the same principle -- get the parts on both ends spinning at the same rotational speed so they can come together non-destructively.

Sorry for the confusion Hawkmoon.  I posted that question hoping for an answer from someone w/ first hand experience w/ the subject. 

ArfinGreebly    

It only takes a few "grinder moments" to act as a learning aid for proper "tone" from the engine (no tach, so you had to use your ears).

This tone ... and believe me it's different in a VW as compared to a large commercial vehicle ... is what I am referencing when asking about Harmonic distortion ... When tooling down the road an experienced driver will quickly recognize which gears they need to use the clutch for and which ones can be easily used w/o .... Although I imagine most here know what I'm referring to I'll try to be more clear.  Assuming I know I can grab 2 - 18 w/o using the clutch my foot would release the 'gas' pedal while moving the transmission out of gear ... coordinated properly the shift out of gear is smooth ... after a moment of neutral  there is a moment of silence (tone) that indicates to the driver that it is time to slip it into the next gear ... I have driven just about every type of large truck/tractor transmission built from 1935-1983 .... Gas or Diesel in a variety of trucks .... I must admit I have spent almost no time shifting a synchronized tranny w/o the clutch.  During the years I was gaining this limited experience I would ask my fellow drivers if they understood what principal was at work when they got that cue to shift while doing it clutchless and never got an answer.  Since there are many smart folks here w/ real world experience I thought this might be the place to get the question answered. 

And Hawkmoon ... I'm sure you're a superior driver and know only other superior drivers ... but if I had a dollar for ever professional truck driver that couldn't shift w/o the clutch I'd be a rich man today ... who knew all they had to do was understand how the transmission worked to obtain a skill many had tried for years to learn. 

[Tallpine]

Well, I tried it once or twice and never got past the getting out of one gear part.  I'm sure it's not just letting completely off the throttle pedal because if you do that then the engine compression is slowing down the rig and there is strain on all the parts.  Someplace between accelerating and slowing down has to be the right place.

It only takes a few "grinder moments" to act as a learning aid for proper "tone" from the engine (no tach, so you had to use your ears).

Well, considering that I was always driving my own truck and I sure as heck could not afford to replace/repair the transmission, I didn't push the learning curve.

I had a clutch and I knew how to use it to shift very smoothly which under heavy loads is the only way to do it and make your equipment last.  The rough roads and hills beat up my truck bad enough as it way.  In 50K miles I probably put 200K miles worth of wear on my engine because I was not very often in high gear.  It was about 70 miles round trip to where I made most of my deliveries, and counting unloading, gassing up, and sometimes collecting a check, it took me about eight hours.

Maybe the clutch-less shifting works better on a level highway, but I almost never saw one.

******************

I don't remember exactly how we were trying to get the F-150 to the shop (until the clutch magically healed itself - apparently there was air in the hydraulics from a long term leak). 

I think we coast started it in third and just planned for daughter-pine to leave it there all the way to town.  I was following with my old pickup so we could push start it again if necessary.  About a mile down the county road she somehow discovered the clutch was working again so she drove normal the rest of the way and we got the leak fixed which was fortunately not inside the bell housing.


When the clutch went out on the old suburban, it was less than a mile to the shop.  The safety switch was disabled so I must have just started it in gear and limped down there.

I used to do all my own work but anymore I just pay to have the heavy stuff done.

[zahc]

It's not rocket science, and I don't see what harmonic distortion could possibly have to do with it. Gears in a transmission are a certain number of RPM apart. When you are listening to the engine, you are just waiting for the engine to slow down X number of RPM until it matches the next higher gear. You can listen to the engine, watch the tach, or simply wait the correct number of seconds. If the engine slowed down instantly you wouldn't have to wait and could just jam it in the next gear. If you have synchronizers you can jam it in the next gear anyway. Synchronizers are devices that allow you to get away with shifting improperly.

Similarly when downshifting, you just have to rev the engine up just enough (but not too much) so that it matches the next-lowest gear.

In either case, if you match exactly, you won't need the clutch to get it in gear. If you are merely close, then you will. If you are way off, it won't go in gear even if you do use the clutch. It seems to me that most people can learn to shift with no clutch shortly after they learn to shift properly with it.

[K Frame]

This morning on my way to work I shifted from second to fifth with no clutch.

Not a problem at all.

One secret for doing it successfully?

Look in your owner's manual for the suggested shift ranges (either MPH or RPM). Almost always those are the "economy" shift points, but they're generally also the points at which you can shift without the clutch.

Secret two.

Once you know where your shift ranges are, do this...

Accelerate a little bit above the shift point. Let off the gas while pulling back gently on the stick. It should slip easily out of gear.

Move the stick to the next gear and GENTLY begin pushing it into gear. DON'T FORCE IT, or you'll grind the hell out of the gears if you skip the gate before things are synchronized.

If you do it correctly, it should slip into gear very easily, at which point you accelerate.


Shifting down is a little trickier because instead of staying off the gas, you have to give it gas to account for the lower gear's higher RPMs. That's when you REALLY need a tach.

[K Frame]

Agreed. Harmonic distortion has NOTHING to do with this process.

And I thought harmonic distortion applied exclusively to sound, not mechanical devices.

[Tallpine]

when downshifting, you just have to rev the engine up just enough (but not too much) so that it matches the next-lowest gear.

I always do that when downshifting so that when I let out the clutch there will be no lurch.

In either case, if you match exactly, you won't need the clutch to get it in gear. If you are merely close, then you will. If you are way off, it won't go in gear even if you do use the clutch. It seems to me that most people can learn to shift with no clutch shortly after they learn to shift properly with it.

If there's any resistance going into gear then I didn't double clutch right and need to do it over instead of forcing it. 

I was taught to double clutch when I drove shool bus about 35 years ago. (well, actually - they took a bunch of us out to a parking lot to practice, and I got it right away and had to ride round and round and round while the other new drivers ground gears  ).  Driving my own medium duty trucks, I just never saw the need to risk damaging something by trying to do it without the clutch.

Shifting down is a little trickier because instead of staying off the gas, you have to give it gas to account for the lower gear's higher RPMs. That's when you REALLY need a tach.

Same thing applies when double clutching downshift.  I never had a tach.  Driving an underpowered truck up steep mountain roads, you have to learn to do it right - or else by the time you get it in gear again you will be stopped or at least need yet another lower gear (if you have any more).

[K Frame]

BAH!

Do it right, do it wrong, doesn't matter!

JUST DO IT! 

The heaviest truck I've ever driven was a 1953 Dodge heavy duty stakebed farm truck loaded with logs. Very similar to this one, actually: http://dodgepilothouseclub.org/dodge/1953_4ton_stake/imgcol/index.htm

Kind of scary coming off the mountain out of the wood lot...

[Tallpine]

Something sorta like this:



I had a semi-tractor swivel log bunk over the rear axle and pulled a single axle army trailer with a fixed bunk, loaded with 20' to 24' logs.  Also had a home built hydraulic log loader mounted behind the cab which added some weight.

GMC 305 V6 had a lot of low end power but was still pretty small for what I was doing.

I don't have any pictures that have been scanned.