So I'm riding with my friend who's a trucker and the guy says, "Why do you keep hitting the clutch when you don't have to?" I says, "In this car you have to." He says, "No you don't." I stops the car and says show me this. And he does it. I did a third to fourth and a fourth to fifth today with no clutch just to see if I could do it. I've been trying for three days. Not all the time, though. I know the synchros don't like it when you're not spot on. Anyway, does this tear anything up? What are the real advantages of doing this for a passenger car?

 

There are NO advantages other than the fact that you can do it where most people can't. There are points in the rev range in each gear where it is possible to do this. Does this mean you should do it on a daily basis? The clutch pedal is there for a reason, use it. We have a syncromesh transmission that likes to fail easily on us. You don't drive an 18 wheeler with a million gears to go through, you drive a maxima.


Every time you do this, and you hear grinding, the input shaft teeth are not lining up with the output shaft gears. This causes stress, and you could crack gears. Ever blown a 4th gen transmission before? Well you will soon if you keep doing this.

 

I dont fully understand how you are actually doing a clutchless gear change, but we have the clutch peddle for a reason, so I think its pretty safe to say that you'll be damaging something by not using the clutch peddle, if that is indeed how its done.

Our trannies are fragil enough as is, no need to put extra un-needed stress on it.

 

Try driving in first gear, slowly accelerating. Put some pressure on the shifter without your foot on the clutch, and it will pull out of gear. If you match it right, it will fall into second without grinding. Good luck getting it not to grind.

 

Sheesh, Mr. Magliozzi. I said that I hadn't been trying it all the time the whole three days. Just once or twice a day, really. And I was never forcing it. I just never believed it was even possible, and this guy did it smoothly as buttah, and if there were any good reasons to do this, I wanted to know. Personally, I'm all about efficiency, and when it takes more than a split second to change gears, I'm not happy. I wonder if there's anyone who can change without the clutch as fast as they can with it, though. I couldn't. And BTW, when I did it successfully a couple of times today, I heard no grinding. Fell right in.

 

in that case you want an automatic with a valve body mod, if your looking for speedy shifting, or custom rig a sequential setup.

but in short, yes you'll be doing damage, it would be best not to do this period, let a lone on a daily basis or every now and then.

I thought that might be the technique... no I like my tranny too much, a lot of us have trouble keeping our trannies lasting just under normal driving conditions.

 

Look at it this way...wouldn't you rather replace your clutch in 50K miles rather than blow your tranny within the next few thousand miles? IMO it just makes sense to use the clutch...it is there for a reason...to shift gears. I am not saying you do this every time you drive the car, but the reason why truckers use this method is because they have 12+ gears that they need to get through. This wears out the clutch easily and if they blow one or two gears, its not a huge deal.

 

I've blown mine twice since the 3.5 swap.

 

my old girl is still holding up but as soon as I have enough funds I'm buying another one, and leaving it in the garage just in case, cause my tranny didnt feel that healthy before my swap, so I dont expect her to last forever.

 

Clutchless shifting is ok to practice every once in awhile just in case you need to be able to do it (I did when my clutch went out on me) but not exactly good for the tranny. It's kind of a novelty though.

 

Yep...I've already got one I'm looking into to buy, I'd rebuild it though and shot peen the gears. It would be worth it. Mabye I'd get some billet stuff made...

 

omg guys.... truck drivers dont use the clutch.... simply because the syncros are so good on trucks that they only use the clutch to get out of first gear... my friend owns his own truck and has over a million miles on it.. He never uses the clutch other than to get out of first....

 

Yes, you can shift without the clutch. But use the clutch. Clutchless shifting can at the very best speed shifts by a tiny fraction of a second, and at worst it will destroy the tranny internals much faster than if you had stuck with clutching. It's least harmful with upshifts at no throttle, if you rev match correctly. So if you try it, make sure to work with the timing and try to get the engine such that it's neither pushing nor engine braking, and push the shifter into gear without rushing it.

The bottom line is that the synchros and gear dog teeth are designed to work with the clutch, such that their loading is caused only by the rotating inertia of the input shaft and coupled gears. If you go clutchless, there is the inertia of the entire drivetrain and torque of the engine loading the shifter parts when you shift. That's a whole lot more load. If you don't rev match perfectly, you WILL wear the synchros and dog teeth very quickly. Your shifts will get clunkier and more likely to grind as they wear.

The kind of trannys that do withstand clutchless shifting are face-engagement (dog box) transmissions. And even then not using a clutch will wear it out more quickly.

So let your friend have fun doing that, but not on your car.

Dave

 

That would be impossible. You have to match the RPM right with each gear to allow it to fall in perfectly. Just a note... that specific rpm isn't anywhere close to redline.

Although it wouldn't be too bad to learn this method. My brother's clutch went out a few months ago and he drove on it just fine by doing this method. Seeing him start in first gear at every light was pretty to watch too. But once moving, he can get the gears to fall in place but it just took some time.

 

Actually OTR trucks do not have a synchronized transmision so that is why they have to double clutch when shifting. If you are talented (usually with many miles under your belt) you can shift without using the clutch. Not all truck drivers shift without a clutch.
My father has been driving for close to 25 years with more than 2 million miles of safe driving and he still double clutches for both up and down shifting. He says that he is just used to it. When he took his Class A driving test they required you to double clutch while shifting.

 

He cannot read what you are telling him.

 

Neither can you.

 

I can!

 

Are you SURE about that?

 

Ive done this in my max by accident once. I was crusing down the road and had my had on the shifter with a slight preasure pulling towards forth, and when i hit (if i remember correctly) 4700 RPM's the shifter just slid into 4th gear.

On another note. when i race my dirt bike, on the take off through the first turn i do not use the clutch just to get faster shifts.

 

My dad taught me to drive clutchless, and I honestly can say that it is absolutely un-necessary. It causes stress on the components as other have mentioned, and it takes a extremely long time to perfect - else you will be blowing trannies to the left and right. Moreover, it is easier to do with a car that has longer plays - i.e. I can shift clutch less in my Scion xB without much effort or resistance... but since I have a short shifter on my Maxima, it does take more strength and concentration.

Bottom line - don't bother... clutch less is only good when you are racing - and even then, chances are you gonna mess something up.

 

I don't think so...

 

Hey I just read the avatar quotes buddy.

 

Not unless you have a dogbox...

 

And if the nickname 'crash box' doesn't give you an idea of what it's like, I'll tell you. Shifting clutchless in a race car is a little bit faster and a whole lot more abusive. Plus any race driver with half a brain will not do it with a synchromesh transmission.

Dave

 

Yep... with smaller engines it isn't as bad, but it's brutal, near-instant change in RPM means a big kick in the pants.

 

Well what I meant is that there is absolutely no benefit for everyday driving.

 

I GUESS that moderators could be banned, but I have never seen it happen...

 

Yeah, my comment was directed to anyone who might confuse the operation of a racing gearbox with the thing in their car.

Entirely different beasts. Different gears, different shift engagement, different costs.

Dave

 

I used to drive a truck and i know why your friend said that, after you drive a truck for a while you begin to find the clutch useless (except for first gear) and when you drive a car you carry over the no clutch habit. I dont, but some truckers do, but like everyone said the clutch is there for a reason and should be used, a trucks tranny is different then our tranny.

 

Okay, we have made our points here...