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Manual Transmission

I have a '98 Wrangler with a 5-speed manual. I was out for a drive with my friend, Irina who possess an impressive amount of knowledge about cars… for a girl. As I approached a red light, I pulled it out of 5th without stepping on the clutch. After years of practice, I’ve developed a technique where I let off the throttle, then a fraction of a second later, I pull it out of gear and coast to a stop. Irina insists that this is bad for the transmission, but I once owned a '79 Toyota, put 150,000 miles on it using this technique and sent it to the boneyard with the original clutch and transmission. The Wrangler has 80,000 miles and the tranny shows no sign of trouble. (Yes, the mileage is correct. I live in Germany and almost never drive.) Am I truly causing damage? Or is the girl wrong.

If you can smoothly change gears without using the clutch, you are bettter than most. I learned to drive in the Army on trucks without synchromesh gears requiring double-clutching.

Your friend has nothing to worry about provided you keep up your precision timing with her distracting you.

I do the same with my BMW 328i sedan. When you shift out of gear, you are disengaging the dogs from the sliders. As long as there is no torque from the engine to the drive train you are OK. If engine compression is slowing the car (or the opposite) torque through the transmission could wear the dogs and sliders. I only do this in 3rd to 5th gear – torque is higher in first and second gears. I time it by lifting off the gas as I shift out of gear.

A buddy and I drove his MG B from MA to FL one spring break. The clutch cable broke 1/2 through the trip and we had to up and down shift without the clutch. Not too hard once you get the feel for it. I never up shift the BMW without the clutch, however.

Twotone

…possess an impressive amount of knowledge about cars… for a girl.

Does Irina know you are a sexist?

While this technique, when done properly, might not harm the transmission, coasting in neutral is dangerous, and in some places, it is also illegal.

Even if it doesn’t hurt the clutch or the transmission, what do you think you are gaining by using this technique?

Any significant torque on the dogs and sliders tends to lock them together and makes it difficult to slide them apart. If pulling it out of gear is effortless, then there is no torque on them and you are doing absolutely no harm to your transmission.

Coasting in neutral is technically illegal in a lot of states but unless it is actually a hazardous situation, nobody cares, not even the cops. Letting a car freewheel to a stop on a level road is not a hazardous situation.

When people are making sense, why question them? I know that it’s your car and you can do all the evil experiments you want, but doing it to a Jeep Wrangler seems like a foolish venture. Take no chances with that thing.

You’re right. I am. After knowing women all my life, I firmly believe that they are superior to men in almost every respect… except maybe killing bugs and lifting heavy furniture. Irina is also a dear friend and we rib each other all the time. After she fixes something on my Jeep that I’ve ruined in an attempt to fix it, I usually say, “Not bad… for a girl.”

As I approach a red light, I can do one of three things; engage the clutch and ride it all the way to the light, run it down through the gears and use a combination of brakes and engine to slow down, or take it out of gear and coast up to the light. Option one is bad for obvious reasons. Option two puts wear and tear on the motor and tranny. Option three takes all the stress off moving parts and puts it solely on the brakes. It puts the least wear and tear on the engine and tranny. Transmissions and clutches cost thousands. Brake pads for a '98 Wrangler are $80 a pair. Also, as I age I’ve gained grains of wisdom. I’ll never be as clever as Irina, but I’ve learned a thing or two. Why rush to a red light? You’re just going ot have to sit and wait when you get there anyway. As soon as I see a red light or stop sign, I take it out of gear and coast up cooly and casually, a light tap on the brake to stop the roll and relax a while. Or, more often, I slow my roll and the light turns green before I even get there and before I stop. And we all know it takes much less energy to accellerate an already moving object than it takes to get one moving from a complete stop. I prefer to spend as much time in motion as possible, thus reducing fuel consumption and wear and tear on the car. With reference to the safety risk, how many of us have been in an accident when we were rolling along? How many of us have been rear-ended while stopped at in intersection? Me? Thrice. I’ll take the risk. And so long as there isn’t a cop riding along with me who’ll know?

I think what may be a factor is where I drive. I grew up in rural Colorado. I now live in rural Germany. I tend to not drive in big cities but usually park at the first park-n-ride lot I see and take public transit into, say Denver. A daily bus and rail pass is much cheaper than a day’s parking or parking tickets. Upon reflection, I don’t think I use this technique in the city because I don’t want the plate disengaged in the event I need to dodge a streetcar or a pedestrian. I only use it on open road or in the small towns where I drive 99.9% of the time.

I let my car freewheel to most red lights unless I need the engine braking to slow down and even then, I don’t downshift through the gears but just use the brakes. Usually I don’t need to brake either with the engine or the brakes because I have that rare gift of being able to see red lights from nearly a half mile away.

Driving habits like that is the reason my gas mileage beats the EPA sticker mileage.

If you do it right every time, it will not hurt a thing, other than maybe your relationship. On the other hand if you miss from time to time, it can do some damage. You can’t really be that lazy that.

BTW what will happen when you borrow a car and find out it does not work quite the same in that car?

I think we’re right in that it’s more efficient to keep an object moving than to stop and go. As soon as the red light comes into view, I pull it out of gear and coast. That drops the engine down to idle and stops the tranny turning. Then, I either gently apply the brakes and ease to a stop and wait, or the light turns back to green and I go from a rolling start back into second or third depending on what speed I’m going. I would suggest that it’s more efficient and less wear and tear than to go up and down the gears at every signal. Granted, it’s easier to do this out in the boondocks where I live than in, say downtown Denver, but then, I rarely drive downtown.

Good question. I tend to not borrow cars. I have a personal philosophy which states, ‘Never borrow anything I wouldn’t loan.’ Another states, ‘Never loan anything I actually want back.’ I never loan my cars, so I would never borrow anyone’s car. Were I to cave, though, I would probably use the clutch unless I had the car long enough to figure out the timing.
By the way, whenever I do it, I hear grinding. It’s Irina’s teeth. I do it less for efficiency and more to annoy her.

Alright, alright. I am informed of a law that I never heard of.
If I am right the term used to describe shifting gears without using the clutch is called “speedshifting”. If a person can synchronize the engine rpm with their ability move between gears it could be considered as less wear on the clutch. I think race car divers used to do this. However, if synchronization is not fully executed correctly harm to the transmission will occur. I personally think you are allowed to perform this action with you own vehicle but not with another person’s vehicle. Once you learn how to perform speedshifting, you can do it with almost any vehicle that has standard shift. No harm, no hate. Oh! 5th gear overdrive may be the exception to this technique as it it more complex to accomplish as a speed shifting situation but it still can be performed.

I realize the danger of coasting is very small. The reason it is illegal in many areas is because with trucks, which don’t have synchronizers, you can find yourself unable to shift into gear in an emergency. Personally, however, I think the first option is best.

I don’t object to you coasting, I just object to doing it without using the clutch, and to a lesser degree, I object to you doing it in neutral.

I should add that my original clutch has 186,000 miles on it.

Riding the clutch? Are you sure about that? I wholly disagree.

If you slip it out of gear when there is no torque on the gears in the transmission it should be no harm and no foul. Yet, I can’t recommend the practice as a general rule. For you it seems to work without damage to your transmission. For others I feel they may cause extra wear and eventually the transmission may slip out of gear on its own.

I’d say to you keep doing it, but don’t teach this to your kids. When they start driving you may end up replacing a transmission or two as a result.

Yeah, there’s a prime moment right when there’s no torque, between the forward torque produced by the engine, and the reverse torque produced after you let off the gas and the engine compression starts to slow the car down. If I pull it out of gear right at the top of that arc, in that tiny little moment, then it slips out with nary a tremor. Too soon or too late and there’s a considerable amount of resistance and there’s an audible, unhealthy sounding thunk.
I agree with you about not teaching it to my daughter. It’s like map-reading. Teach her to use a map and compass first, THEN give her a GPS.

That is not “riding the clutch.” Riding the clutch is when you never take your foot all the way off of it, so it never fully engages. I agree that riding the clutch is bad for it, but that is not what I am suggesting. I am suggesting you coast with the clutch fully applied (fully disengaged) with the vehicle in gear. It won’t hurt a thing.

For a full explanation of the term “riding the clutch,” see http://en.wikipedia.org/wiki/Riding_the_clutch#Riding_the_clutch

True, that. But then you have to downshift, go back down through the gears to a stop. I still assert that it’s less wear and tear and consumes less fuel if I take it out of gear, let the engine drop to idle, disengage the transmission and roll to a stop using the brakes. I think we may have to simply disagree, which I hope we can do without becoming disagreeable.

No problem. We can disagree. Many people I respect have said in this thread that you can get away with doing this without causing damage if you do it correctly. I am just left wondering why? What is the benefit? Where do the fuel savings come from?

I would like to add that almost every fuel injected engine made in the past several years will shut off the supply of fuel when you coast in gear. When you take it out of gear, the engine must use fuel to keep the engine running. Even if your 1998 Wrangler isn’t new enough to have this fuel shut-off feature, surely it uses less fuel when coasting in gear than it does coasting in neutral. I am not saying you should downshift through the gears, but I do think you should keep it in the current gear longer and use the clutch to take it out of gear. You have nothing to lose, and you will save fuel.

I am puzzled as to why you asked the question in the first place. You appear to have already made up your mind before you asked the question.