Is Double-Clutching "Bad"?

I get your analogy, but release the can clutch and stick you fingers in quickly. Same thing will happen.

In either case the speed of the input shaft MUST match the speed of the gear it is going into. Clutch in or out, hence it does nothing for the actual shift.

 

Dc is the beginner method of shifting. It is not bad nor good. shift the way you know.period. If you want to learn the alternative method of clutch less shifting, that is fine too. But don't be concerned about it until you have 20,000 miles or more of driving experience. You need to have experience before you teach yourself to float gears. After you get good at dc shifting, the next step is to go to single clutching. Once you are comfortable with that, the next step is to float the gears. You will find that when you are single clutching that there are times you can pull the shifter out of gear without using the clutch......your first clutch less shift!! Up shifting is easier than downshifting, as you have mentioned, so floating on up shifts is the easiest way to start.

my boss wanted me to learn to float the gears, so I did. But driving interstates don't give you much opportunity to shift. I learned how to shift driving local roads that are one mile square in ia. You turn, run through the gears, and then turn in a mile and repeat....excellent way to learn shifting as that is all you do on those 1 or 2 mile roads. I could haul a load of corn from the farm to the co-op without using the clutch, up shifting or downshifting as needed. I would have never been able to learn floating so fast without the local gravel roads to drive. It was a great learning experience for me.

 

I'm sure you understand then, if for some reason the speeds aren't exactly matched, there's lots more potential for damage without the clutch.

 

Never have double clutched haven't seen the need for it let alone the unnecessary wear on parts. That being said I have bumped the clutch once in an off-road heavy condition a time or two.

 

Very true.

 

I'm no super trucker technically speaking the company I work for doesn't even label me as a trucker. I'm actually a sales servicemen because of that I'll take an automatic ha-ha! You got one I'll take it trust me between watching the traffic and monitoring my mirrors I have plenty to do.

 

If your smooth at floating the gears just use the free play of the clutch to pretend to double clutch.. Although I can do both I did use this method to pass first road test, also helped others pass theirs same way... It is good to know how to do both as sometimes it seems better to double clutch.. Just my .02

Some may disagree with me or call me crazy but I feel every truck has its own personality.. Takes a min to find how the truck likes to be shifted but soon can go just by the pitch of the engine to know when you hit the sweet spot for the gear to fall in.. Before you know it you will be going down the road and go to put it in the big hole only to realize its already been done.. Becomes second nature on not much thought goes into it when driving on flat land when you been in the same truck for awhile

 

You'll learn to float. The bigger the machine, the lighter the touch is needed on the controls. Think of your truck as your woman. Does she like to be shoved around? Easy on the touch. You'll get to where you'll feel the gears & synchro's without grinding the crap out of them. This is why everyone should be a company driver to start. You'll use your clutch for starting, and stopping, doubling on grades. It gives you a fraction more time to get her in gear than a strait float. Clutches ain't cheap. Floating properly will save you a truck load of money.

 

As a trainer we are supposed to have all our trainees DC. Most trainees that get on the truck have about 10 hours behind the wheel, so they are pretty raw. Usually by the 2nd or 3rd day I have them try and float a few gears in high range to get the feel of it, mostly to reinforce how LITTLE you need to move the throttle to get the right rpm so the gear goes in like a hot knife in butter. Until then it's a racking experience as they ramp up the rpm's to the red line, hold the shifter in neutral position after clutching to get out of gear, then let their foot ALL the way off, then do the full on Mohammed Ali jab for the gear hoping against hope they make impact in the split second the rpm's are going to be right... somewhere between 2200 and 600 rpm's...

I've also had experienced drivers who have had time off from trucking who had to train in my truck. Even they can be fairly brutal on a drive train, stomping on the accelerator after engaging each gear instead of easing into the throttle, and that drive train is torquing back and forth like a kid in a bad divorce.

DC isn't the end all answer to being easy on a drive train. Being easy on the throttle and easing it into gear at the correct rpm is the answer. If you do that then DC is the "right way" according to all the manuals that come with your truck.

Make sure when you DC that you only tap the clutch in a maximum of 1". Even experienced drivers that double clutch are pushing in the clutch WAY too far. Then you'll end up doing significant damage to the drive train.

All that being said, I float 95% of the time, "tap out" on a sticky gear about 4% of the time, and DC about 1% of the time. Floating in heavy traffic makes it go much much easier for me.

 

I was fortunate to learn to drive in cattle trucks. There you have to shift and drive smooth or you will have problems with cattle splitting out or being knocked over and trampled on and end up dragging them off the trailer with a chain.
To me everytime you use the clutch there is a lil slippage and slippage is wear.. Call me old school but just how I was taught.
I taught a few drivers how to drive so they could go get their cdl and help farmers during harvest.. 1 I spent 5 days rolling around the coop parking lot having him upshift and down shift in low range. He kept asking me when we were going to hit the roads and I informed him I would not be in the truck with him going down a road at any speed until he learned to upshift and downshift in low range. It was quite amusing watching him do everything but stand on the shifter trying to get it in gear, then telling him what rpm to hit and it fall in.. By far the most stubborn person I ever taught.. To this day I still call him muscle man because of him trying to muscle the truck in gear