Clutch or Float Gears
 

This is my last week of schooling, before I test for my CDL on Thursday. The school claims 200 hours of training but I find myself sitting around more than I train. There are only nine students in my class. Time is wasted waiting for students to show up in the morning. Instructors being fired, showing up late or calling in sick. The ones that do show up do OK, they give good instruction, they just don't seem to be motivated to go the extra mile so we can get in driving time. I am learning in the trucking world that if you have inclement weather, rain, you shut down. The lightening I understood, but rain? Anyway, the whole point to this post is I am getting very little driving time. I can back, I have done well since the very first time, I have done backing ad nausium for the last two weeks. It is better than no driving time. Some of are playing games now, challenging games. We straight line back and parallel park. We have started moving our marking cones in until we hit one. I can parallel in a pretty tight spot now. On the road driving is the problem. I haven't had enough time behind the wheel. With experience I will get it down. I'm sure I have had less than three hours total out on the road. It is very frustrating. I am having problems down shifting. It just doesn't make sense to brake to slow the truck down then step on the accelerator to shift. That and the fact that air brakes lack the precision that hydraulic brakes do. So, my question is that in the limited driving time I am likely to get in the next three class days before the test should I try to learn to float and am I likely to downshift better floating? Or should I just stick to double shifting, which I'm better at every time I drive? The instructor did say I would pass the test at my present level of skill, I am not satisfied though.

What school are you attending??

International Schools at Austin Community College in Austin, TX.

If you can't find it, grind it! :D

Just rating myself, I would say I can downshift properly better than 75% of the time. Maybe another 20% I have slight trouble with and occasionally I can't find the gear at all. I almost always know why I have trouble. I do admit while driving I will set up situations where I am downshifting without needing to, just to practice. On the day of the test I will downshift as little as possible. I will up shift as little as possible.

If it makes you feel any better, I've been driving for years, been a trainer, own my own truck (and you'd think I know ALL the in's and out's of my own truck), and there are times when I miss a gear on the down-side. And, after all these years, I DO use the clutch ALL THE TIME. I could float the gears, but I can shift FASTER by using the clutch. I've been accused of shifting like I'm in the INDY-500.

Use what seems to work the best for you. When you ask here, you'll get a variety of opinions. But going down the road, none of those opinions will be driving your truck or doing the shifting. Use what works best for you, and don't fix it if it ain't broke.

Floating the gears does not make you a driver, and using the clutch also does not make you a driver.

I understand all of this, I do not beat myself up because of my mistakes. I think I am doing remarkably well for the limited time I have been behind the wheel. My question is, in the very limited time I can expect to be behind the wheel in the next three days, about three hours if everything goes right, should I just stick with double clutching, which I have been doing or should I try to float. I do pick up thing well and other aspects of driving the truck are not giving me problems at all.

Until you get out of school, or even until you are hired and "trained" (don't know who you're going with, so I don't know if you'll really have a trainer or will be "self-taught".) You'll have plenty of time later to learn all the "bad habits". You've been double-clutching? Stay with it until you get out on your own. Then, try "fixing what ain't broke". I have heard of guys that did not get their CDL after they tested with DOT because they didn't "USE THE CLUTCH PROPERLY". Might depend on the state and how the examiner feels that day... I don't know. I'd suggest using what you've been doing for now.

At my school they actually told us not to double clutch when downshifting...all you have to do to downshift is to take your foot off the throttle while pulling the stick out of the gear and move the stick into the 'smaller hole' as you bring your revs up gently. Soon you will know how high the revs need to be to slide in.
As for upshifting, i usually skip gears unless im going up a hill heavy...with a super10, I start in 3rd, then 5th, 7th, sometimes then 8, 9,10 with my jake on low so the revs drop faster during shifting.
To upshift not using a clutch simply accelerate to the shiftpoint, pull the stick out as you let off the throttle, and ease it in the bigger hole. you will feel a slight rubbing of the gears. if the rubbing is slowing down, youre getting to the right rpm for it to drop in, if theyre speeding up, you've done passed it...you should never have to use force, it can be done with 3 fingers! As you get proficient, no gear 'rubbing' should accur...
you will soon get a sense of how long it takes for the gears to slow down to where the stick drop right in! Ironically it takes about the time for you to doubleclutch...When going downhill or uphill the truck's acceleration/deceleration due to grade will affect that too. Id say doubleclutch on grades till you get the hang of it.
Im pretty sure i told you everything you need to know, maybe someone will amend to this...Good Luck and ask if you have Q's

Windwalker has a point, learn to doubleclutch first, because you will have to do it during road-tests!!!
But keep what i said in mind...Basically you are doing the same things when doubleclutching, just not actually moving ur leg...

For the test, do what you are the best at. All you HAVE to do is pass. :D

Downshifting
 

I am still in school, a community technical county school (PTEC) and it is our instructor who will test us. He says don't worry about shifting while stopping. Just worry about getting it to stop safely. He says he would rather NOT see us downshift at all, just stop. On upshifting we must double clutch for him.

Re: Downshifting
 

My problem on down shifting is the closer I get to my stop or turn. When I still have some distance I seem to do alright. As I get closer it defies logic to take my foot off the brake to rev the engine. We are using 9 speeds. The instructor showed us a neat trick, I don't know if it common knowledge or not, when down shifting in high range, high range low is the same as low 4th. It is much easier to find high low than it is to find 4th, and 4th can be used for turns.

It does, indeed, work on a 9 speed. The granny-low hole in high range gives you the same speed as the high-hole in low-range. I believe it also works on a 13-speed. Been a while since I drove one of them. It does not work on a 10-speed, or super-10.

Once you get out of school and in your own truck, shifting will become second nature. The more you worry about it now, the worse you will make it on yourself. Just let it come to you, and it will.

Re: Downshifting
 

You are not supposed to the low position while in high range according to Eaton Fuller.

Yeah, if everything goes right I'll be working for TMC. Then I'll have to learn a 13 speed with a splitter. Will it ever end?

Re: Downshifting
 

You're right. You are not supposed to use it. However, I know of quite a number of drivers that do use it, and there has not appeared to have been any damage done to the transmission.

The company just traded in their day-cab, with a 9-speed. The driver has been in that truck since it was bought. Now, he's got a 10-speed and is complaining that he doesn't have that "extra hole" to use. I drove it last month, and there didn't seem to be anything unusual with the tranny. Over 700K on it, and the tranny has never had to have anything done to it. I know what Eaton-Fuller says, but........

A few observations on the 9LL Eaton Fuller.
-the gaps between gears is about 500 vs 400 for a 10 sp
-downshifting is at 1000 for 8 to 5, rev, then shift down
-from high 5 to low 4 I drop to 800 rpm and give it a stronger rev
-4 to 2 drop to 1000 rpm then rev and downshift

The timing of the shifts and clutching also depends on the weight being hauled...
-empty, the truck slows more between shifts requiring slower shifts.
I listen to the turbo spooling down to judge shift timing.

The odd thing in my truck(electronic fuel pedal) there is about 3/8" free play before rpms increase making it difficult to apply fuel smoothly.

Whatever works for you. I personally float while shifting. I work with guys that clutch. It just depends what you feels comfortable with.

Re: Downshifting
 

[quote="Overloaded"]
800,000 on my 13 and thats the way its been drivin since new. i do it and ther owner did it when he drove the truck. i donno mabey its just luck.

Well, I stuck with double clutching. It seemed to come together this week. I haven't had any major problems. If I loose a gear, I can put it in another pretty fast. This is a good thing, we were told we are testing a day early, surprise, surprise. It is supposed to rain tomorrow. This might be fun.

Now we are up to 80% chance of rain throughout the day tomorrow.

Re: Downshifting
 

I usually do not bother downshifting more than 2-3 gears except for turns...its just unnecessary work on your poor joints...

I use the clucth for starting and stopping only. However, when I first started learning to drive, I'd use the clucth every now and then if I got jumbled up shifting and it would save my momentum and find the gear. Learning the different points where the shifts are smooth as butter is part of learning to drive, and did not come that easily for me, but practice made perfect 8)

this is probably too late but down shift one gear at a time each time your tachometer reaches 1200 rpm's. Use your clutch to take it out of gear then just bump the rpm's up a little and give the shifter a little pressure towards the gear you want at the same time and it will slide right in I guarantee it will work on that 9 speed.

I took my driving test today, and passed. It was raining a little, the roads were wet. We had the airbrakes, backing and road test today. Everyone passed the airbrakes and backing only four of us took the road test, the others will in the next two days. Then I had to go to DPS, get my license and start the HAZMAT process. I should be at TMC November 6th or 13th. I hope to see some of you up there.

Just my .02 from a rookie.....I just took my test 2 weeks ago and I was concerned about this just as you are. I asked the instructor what they wanted me to do and explained I could use the clutch but was better at floating the gears. She said to me that it is not required to use the clutch and to do whichever way I know best....that is how I would drive on my own and be the safest. Also the test was as easy as everyone told me it would be and even though I was confident in knowing what I needed to, I worried about it more that I needed to. My point is if you have questions on how they want you to do it, explain you can do both but are better doing it a certain way. The testers are everyday people, not drill sargeants with whistles and superpowers. If you are confident in your ability and knowledge, relax...you'll do fine.

Thank you for your advice, but if you look at my post just above yours, I have already taken and passed the test. :D

Re: Clutch or Float Gears
 

In Georgia, State Examiners do not allow floating. That said, downshifting with a half a double clutch is acceptable and I often find it easier.

I'd suggest going with what you know best, and when you get with your trainer on the road, do as he wants. Later you can decide.

As for me, I float, but occassionally clutch depending upon the situation. And for downshifting I often do the half double clutch.

[Yeah, I know, a half a double is a single. To clarify, I mean that I clutch into neutral, then float to the next gear I'm going down to. Make sense?]

All the best, Tee

8)

Here's an entertaining video displaying proper clutch usage... :twisted:

http://youtube.com/watch?v=vxkQmcDsulU

(extra credit for running over any maniacal bystanders :twisted: )

Proper clutch/brake/accelerator usage yes, but I didn't see any double clutching.

Back when I was in School, and didn't know squat, they said, "You will Dbl Clutch ONLY here!". As a part o the Classroom Portion, Shift points @ RPM vs Groundspeeds were stressed like nobody's business - (on a Straight 10 Eaton).. I learned well how to Dbl clutch. During a Road Session, at a location too near where the Master Instructor told us not to be, the Clutch Linkage BROKE. Long story short: I got my first lessons in Floating when the Driving Instructor had to take the wheel... (I had to come to a stop/ red light intersection/ downtown traffic/ newb/ etc).
That sucker Started the Freightliner FLHD in 1st gear - and floated us home to base. ("We ain' gonna sit here no 2+ hrs waitin' on no Mechanic/ Tow truck. Here's why you at least better 'know' how to Float.")
After hiring on to my current Company, I did 4 weeks out with a Damn Good Driver Trainer and learned well how to float.... (And Right Here is where all that hammering on RPM vs Groundspeed/ shift points paid off!)
Nowofdays, after 20months solo behind the wheel, I float up or down most of the time. Howeverso--, each and every time I get in a bind, ('torque-locked driveline', uphill/downhill loaded/unloaded, exhaustion, whatever), I automatically go into Dbl Clutch Mode due to my training and it's saved my rear many times....
So I'll say this to you: LEARN and make Dbl Clutching an instinctual Basic Move. I got a feeling you'll be schooled on the Float at a later date... Dbl Clutching is the best way out of trouble in consideration for the mechanical components in the Driveline and in consideration for the Human Condition. Yo Brain need to be working to Float properly and well... AND.. Yes, it's the only thing that'll get and keep you rolling when clutch probs ultimately arise. :wink: There are simply Some Places where you don't want to be stranded just on account o busted clutch components, etc. :mrgreen:
It's all a bit o WORK, .. but you did come to work, didntcha? :shock: