"Floating" the gears

[JSontag]

Ok pros, let me know something about the subject.
Been trying to find a description on how it´s done but haven´t so please tell me step by step how you do it! :thinking:
I know A LOT of guys and gals do it so I figured there is someone here who does it too...Oh and btw, what´s the benefit of doing it? :wow:

floating the gears if your talking about shifting with the rpms
just watch you rpm gage and listen to your engine when you enging strats to whine and your rpms are around 1800 then you can catch the next gear as to benifit saves the clutch for when you really need it

[JSontag]

But what about different engines and trannys? Does the rpms vary or something? Is there a difference between a 10-spd and a 13-spd? Or is it just basically the same with all of them? (Don´t worry I´m not going to go break someonce tranny tomorrow :) )

[Bikerboy]

hey ironeagle, you forgot to talk about letting the rpms drop to match the gear speeds.

I usually float gears all the time, just once your ready to shift. As soon as you let of throttle, you must pull shifter into neutral at the same time, or it will hang in gear. Then once your in neutral let rpms drop about 300- 500 rpm from where it was before you started the shift. Once the rpms have dropped( about 1-2 seconds maybe) try to shift to the next gear, push gently, if it grinds or hangs up, keep adjusting rpms with throttle, until it will slide right in.
Don't force it! or you will break stuff.

When your downshifting it is a bit different, cuz you must rev up engine 300-500 rpms to match gear speeds.

It's all about having a steady and gentle foot on throttle and shifter.

If you still have trouble sometimes i will single clutch once i have it in neutral , just to get it back in gear easier.

You really don't need to clutch to shift into neutral, you just got to time the shift , at the same time as your letting off throttle.

But what about different engines and trannys? Does the rpms vary or something? Is there a difference between a 10-spd and a 13-spd? Or is it just basically the same with all of them? (Don´t worry I´m not going to go break someonce tranny tomorrow :) )

ok take the truck in my sig line it has N-14 cummins with a 10spd and shifts at 1600 rpms the truck engine will tell you when to shift is what i was getting at but usually you can sift at 1800 but no more then that

[JSontag]

Ok, I think I know (in theory) how it´s done now. 1600-1800rpms sounds really low, I figured that you would change around 2000rpms(I´m not a truckker so I don´t know). Well it seems I learned something new again....... :p :p :p

hey ironeagle, you forgot to talk about letting the rpms drop to match the gear speeds.

I usually float gears all the time, just once your ready to shift. As soon as you let of throttle, you must pull shifter into neutral at the same time, or it will hang in gear. Then once your in neutral let rpms drop about 300- 500 rpm from where it was before you started the shift. Once the rpms have dropped( about 1-2 seconds maybe) try to shift to the next gear, push gently, if it grinds or hangs up, keep adjusting rpms with throttle, until it will slide right in.
Don't force it! or you will break stuff.

When your downshifting it is a bit different, cuz you must rev up engine 300-500 rpms to match gear speeds.

It's all about having a steady and gentle foot on throttle and shifter.

If you still have trouble sometimes i will single clutch once i have it in neutral , just to get it back in gear easier.

You really don't need to clutch to shift into neutral, you just got to time the shift , at the same time as your letting off throttle.

your right i did forget about that bikerboy thanx for adding that

if change at 2000 rpms you risk hurting the truckso keep it easy 1600 to 1800 is ware i shift at

[Bikerboy]

Some engines run higher rpms that others too, i drive a dt 530 international sometimes, and i always shift it at about 2000 rpm, cuz any lower and theres no torque. When that truck is running 65 mph, the engine is revving like 2300 rpm, hasn't hurt it.

[liner]

With todays high-torque low RPM engines there is no need to shift at such high RPM's.When starting from a stop all you need is to increase your RPM ever so little to grab the next gear.As you pick up speed increase your RPM a bit more depending on the weight of your load.If you have a new high torque engine you don't have to get even close to 1600-1800 RPM's to shift.Depending on the tranny and rear end ratio you shouldn't have to get your RPM's much over 1300-1400 in order to shift.Anything above that and your just blowing $$$$ out the stack.Its called "progressive " shifting.
These new engines can lug back to 1000-1100 RPM's without hurting them.
NOTE:Not all trucks are geared the same so this theory won't work for everyone.















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[Big_Dave]

On my 3406E Cat, the 'sweet spot' is between 1200-1600 rpm's.

The only time I'll run the rpm's higher while accelerating is if I'm loaded heavy and climbing a get-on ramp. I got 3.08 rears and she has a hard time pulling hills unless I keep 'er wound tight. ;)

[JSontag]

Those rpms are really low. :wtf: It seems I had the wrong image in my head or then I was just thinking about those old trucking movies where they have thick black smoke coming out of the stacks ;)

[Big_Dave]

You're thinking of the old days with the screamin Detroits and such. Back then the only way to get any performance out of them was to wind 'em up tight and keep 'em that way.

Todays engines are high torque / low rpm motors. 1000 to 1600 rpm's is pretty much all you need anymore.

I can lug my Cat down to about 1100 rpm's when fully loaded and she'll pull like a dream.

On steep inclines I keep 'er wound tight because of my rear end ratios. I loose too much rpm's and have to drop grears faster than hell if I let it lug on steep grades.

I've climbed Cajon Pass (coming out of Los Angeles), loaded to 80K lbs., in 5th gear @ 1800 rpm's just to keep the motor from overheating. She'll do it in 6th, but with the lower rpm's, the fan can't keep the motor cool.

[allikat]

I found it easy enough on almost any truck.
Just takes about 5 minutes to get the timing right.
I pull it out of gear, hesitate a moment in neutral, and slip it into the next gear, works nearly every time, and I've driven trucks from 21 years old to nearly new! 9 speed boxes right up to 18s. Seems to be a little easier on a 13/15/18 speed because the splitter mechanism helps the shifting.

[Foxfire]

The best thing to do is listen to the truck. It will tell you when to shift. I haven't watched a tach in so many years it's not even funny.

[Maverick]

When I read the question I did'nt think that anyone would actually be able to explain the process well enough in writing to actually teach someone how to "float the gears" but I must say, you all did a great job!! :cheers:

[Lexy]

I know A LOT of guys do it.........


Ahhh hummmm

A lot of us girls do it to.


Floating the gears is how hubby taught me to shift. Other than start/stop, if I had to use a clutch, I would be in a fix!

I'm glad these other folks could explain it to ya, cause there is no way I could have. Hubby didn't teach me by the tach, he taught me by listening to the motor.

Ya talkin about bein messed up? Try going from a 350 Cummins to a 3406 Cat... :wacko:

[JSontag]

Ok I corrected the first post, my bad.......... :paranoid:

[Jimbo]

If you need the clutch to shift, you have some learning to do yet. The only time I ever touched my clutch is when I was starting out at a traffic light. Once you learn to do it, it's easier than using the clutch.

[JSontag]

If you need the clutch to shift, you have some learning to do yet. The only time I ever touched my clutch is when I was starting out at a traffic light. Once you learn to do it, it's easier than using the clutch.

Well since I´ve hardly ever driven a truck I got a lot of other things to learn too. :p
Actually I drove a dump truck for some time but that´s allready years ago. It was just temporarily when our driver was sick.

[allikat]

Jsontag, you'll also need to know that US trucks use a constant mesh gearbox (like the old Eaton-fuller twin-splitter) unlike the synchormesh boxes used commonly in Europe.

You can float a roadranger, try it in a brand new Scania and you'll roll to a halt with no gearbox.

[truckerdale]

My turn .... I happen to own one of those Detroits,,, 8V92T (federal version) 445 ponies ,, floating gears ,, do it all the time ,, clutch is for stop lights/signs ,, also it is not a foot rest ,, max "r's" 2350 and that is a screamin' demon ,, normal cruisin' right at 2000-2100 ,, ease up on the fuel feed ,, out of that gear directly into the next higer gear ,, ease back into the fuel feed ,, over and over till the top or wherever you want to run it at ,, going down just the opposite ,, if you have a "jake" it can make it a lot easier ,, a whole lot easier,, about hills ... never go down a hill in a gear that is higher than the one you went up the hill in (that was what I was taught) ,, I have a very interesting lengthy story about the "grapevine" and gears ..........

[Chiefwhatdahey]

My turn .... I happen to own one of those Detroits,,, 8V92T (federal version) 445 ponies ,, floating gears ,, do it all the time ,, clutch is for stop lights/signs ,, also it is not a foot rest ,, max "r's" 2350 and that is a screamin' demon ,, normal cruisin' right at 2000-2100 ,, ease up on the fuel feed ,, out of that gear directly into the next higer gear ,, ease back into the fuel feed ,, over and over till the top or wherever you want to run it at ,, going down just the opposite ,, if you have a "jake" it can make it a lot easier ,, a whole lot easier,, about hills ... never go down a hill in a gear that is higher than the one you went up the hill in (that was what I was taught) ,, I have a very interesting lengthy story about the "grapevine" and gears ..........

I had two of them motors in two seperate trucks I can always tell by the sound when there is one in the vicinity. A quarry I used to work out of had a V16 dump truck now that was loud. I wouldn't put a jake on a screamin D it's hard on the wrist pins

[truckerdale]

Gotta have that jake, rebuilt mine with the latest mod kit , works great , HINT make sure your mech doesn't get distracted while setting the clearances ,, mine did that ONCE Cum-a-part specs work really good on a 92 ,, until it breaks a valve stem 'cause they are to tight ... wahhhhhhhhh !!!!!!!!

[Bikerboy]

i have also driven a screamin detroit(6V53) . It had a auto tranny and the truck only had oil pressure and engine temp for gauges, no speedo or tach. It was one wild truck to drive, just hold it too the floor all the time and once i revved high enough it would shift. Thing used about 5 litres oil a day!

[nitestar]

Floating the gears.

Well I do the rpm thing myself. With a 13 speed tranny
you will have a 300 rpm drop if you are splitting the pattern. Watch the gauge and shift at 300 rpm drop.( all rpm are approximaten but close)
If shifting a full gear use the 600 rpm drop. .
It isn't as important what your max rpm is it is what you are shifting at.


300----600.
Good luck , safe trucking.

[itrucker]

Learning how to "float" the gears is fairly simple. But it requires some practice. All ya gotta do is borrow someone else's truck! :D

Seriously, once you get the hang of it, it becomes 2nd nature. Heck, I even can do it in reverse using the splitter button. Not! :yikes:

Keep in mind that most companies (if you're a company driver) discourage the use of floating the gears. They of course would rather replace the clutch than the tranny!

- Chris

[allikat]

yeah???
The Roadranger box is built like a tank! It's almost impossible to destroy them! The farm company I worked for insisted you float the box (which helped as most of the clutches were pretty much shot anyhow...)

[itrucker]

Good ole English know how! Heck--who needs a clutch anyways! :rofl:

Across the pond, you'd see corporate management's faces go white as a sheet if anyone encouraged drivers to float the gears as official policy. :D

[The Saint]

The other thing to remember about floating the gears is that if you have the jake on you have to either turn it off or don't take your foot completely off the throttle...just enough to keep the jake off. You will miss the gear when the jakes engages in the middle of the shift.

[JSontag]

The other thing to remember about floating the gears is that if you have the jake on you have to either turn it off or don't take your foot completely off the throttle...just enough to keep the jake off. You will miss the gear when the jakes engages in the middle of the shift.

Another good lesson learned. :cheers:
Never hurts to ask because you always learn something new :classic:

[Bikerboy]

Sometime i forget to turn off jake, and i shift up threw the gears fine, then other times i will keeping missing gears and i dunno what is goiing on, then i remember jake.

As long as you shift fast enough it will shift ok with jake on. I downshift with it on sometimes too. Works ok most of the time.