Want to get a little confused?
How about learning how to drive an American heavy truck non-synchromesh transmission - like a 10, 13 or an 18 speed?
I bought my first semi tractor (what you guys call an articulated HGV) in 1974. It was an cabover International with a 318 Screaming Jenny - i.e. a Detroit 318 HP two stroke V8 engine - very much like this one:
https://www.youtube.com/watch?v=gFcjM3eO-Rg&t=24s
(This one has a 13 speed and the driver is cheating - he's using the clutch)..
Mine had a 10 speed Eaton Fuller transmission but I had gotten my trucking license on a 10 speed Spicer transmission and although they had the same amount of gears, how you shifted those gears was very different.
The Spicer was basically a 5 speed transmission where you "split" every gear position - i.e. 1/2, 3/4. 5/6, 7/8 and 9/10.
The Fuller you go 1, 2, 3, 4, 5, split to upper range and then do the same 5 gears which then are 6, 7, 8, 9 and 10.
I had an interesting first week before I got used to the Fuller transmission.
After a while I learned to "float" the gears - i.e. you only used the clutch when you started rolling - the rest of the time you shifted by synchronizing the road speed and matching the proper gear and engine speed.
How to do it without the clutch -
https://www.youtube.com/watch?v=uwjIJLnzP8Q
Here's is a 13 speed Kenworth 318 conventional (long nose) with a Jake brake:
https://www.youtube.com/watch?v=98CTHm3Xn0Q
Jake Brake:
https://www.youtube.com/watch?v=qocMoTOVn6Q
The 318's were high revving (2,500 rpm) engines. They were very reliable engines - but noisy and thirsty - you were doing good if you got 5 miles to the gallon but then fuel was cheap.
There are a lot of them still running in Mexico.
My later trucks had 400 and 450 Caterpillar engines.
The 13 speed has the super low (1), then 4 gears in an H pattern, 2, 3, 4 and 5 - you then go into upper range and in each position of the H you have an overdrive - think 6/7, 8/9, 10/11 and the last H position is 12/13.
Confusing, right?
Shifting it - you either double clutch or float - and floating is much smoother and easier on the transmission and clutch and you shift up or down using the rpm's - the accelerator (gas pedal) controls up and downshifts as you move the shifter and splitter and of course the speed.
If you do not shift at the exact right moment - especially if you're loaded - you won't be able to move the gearshift without using the clutch - the transmission will simply "hang". I've seen 250 lb guys break out in a sweat and still not being able to pull the gearshift out of the gear they missed - and still if you knew what you were doing you could shift the transmission with one finger - like a knife cutting warm butter..
My next semi had a 13 speed Fuller, next one a 15 speed.
There was also the 4x4 two stick 16 speed and the 18 speed, the 9 speed, the 7 speed and more..
Nowadays most semis on the roads in the states have 10 speeds because the engines have such a large torque range and they are much lower revving - think 1,800 max but optimum range is 1,200 - 1,500 depending on the engine.
If you want to get *really* confused - watch this guy:
https://www.youtube.com/watch?v=LzB9vZ71v08
If you don't get it - don't feel bad - this is about the worst explanation of transmissions I've ever come across.
He does explain progressive shifting/power band on today's diesel fairly well..
Today large trucking companies want teams - and especially married teams - and in order to get those drivers they buy auto transmission trucks so new drivers don't have to learn to shift non synchro transmissions.
Of course this severely limits the job market for these drivers - "You can't drive a manual transmission? Sorry Bud - no job for you."
Add to this that there's a catch - "we train you to get the license - and you agree to work for us for a year at very low new driver compensation - and if you quit before the year is up you owe us $5,000 for the training."
Perhaps that's one of the reasons there's a huge shortage of truck drivers in the states:
https://tkographix.com/need-a-job-th...50000-drivers/