It's a nine speed transmission, so see the related link for a diagram. The diagram is actually of a 13 speed transmission - the difference with the nine speed is that it doesn't have the High/Low settings for the top side. The nine speed "H" pattern is the same basic pattern used for the 8LL, 13, and 18 speed transmissions.
It's the same as the shift pattern for the Eaton Fuller nine speed transmissions, albeit with additional gears on the low side. For the sake of not wanting to type out a long winded explanation, there is a related link posted - 'Eaton Fuller 18 speed shifting diagram'. Click on that link to see a visual representation of the shift pattern.
Same shift pattern as a 9 speed. Youtube has a great video straight from eaton fuller on it that would be better than me typing it.
Keep rpm between 1400 to 1600
I've never heard of an Eaton Fuller 12 speed, nor am I able to find any references to one via Google. I've driven Eaton Fuller 8LL, 9 speed, 10 speed, 13 speed, and 18 speed transmissions - could you be thinking of one of these? IIRC, Volvo marketed a proprietary 12 speed transmission, and Meritor offered a 12 speed automatic, but not Eaton Fuller.
Depends on model and transmission. On most KW trucks, there isn't one. If you have an automatic, then it depends on your transmission, e.g., Allison, Eaton Smart Shift, Meritor, etc.
On an unsynchronized manual transmission, you either have to double clutch (which will be required on any road test or "float" the gears. For the actual shifting patterns, diagrams should be readily available online.
Could be a few different things. Bad shift forks would be the most likely culprit if it were a manual transmission. For an auto, probably either a faulty transmission ECM or worn synchronizer gear.
No you cannot change a 13 to a 18 speed, however you can change a 18 speed to a 13 speed just by changing the shift knob.
No you can not, it is a different transmission. The 18 speed has a splitter for the lower range as well as high range.
The best way to learn this is to have someone show you how. You're not going to learn this by just reading about it. A general rule of thumb is to downshift at 1000 RPMs, or 700 RPMs if you're dropping two gears. You would clutch, shift to neutral, hit the accelerator pedal, clutch, push it into the next lower gear at 1500 RPMs. This is a default taught at truck driving schools, and is not ideal for all engines and terrains. In soft dirt or soil, you'd downshift at a higher RPM, but you have to get accustomed to synchronizing your shifts yourself before you figure that part out... the manual transmissions (with the exception of the Volvo 14 speed) on Class 8 trucks in North America do not have a synchronizer gear, and the driver has to time their shifts in order to compensate for it. This is true whether the transmission is Eaton-Fuller, Rockwell, or a proprietary Mack transmission. If you're looking for the shift pattern, we'd need to know the make and model of the transmission. I'm willing to bet the transmission is most likely an Eaton 9 speed or 8LL, but the pattern depends on the model... a double overdrive transmission has a different shift pattern than a direct drive or single overdrive transmission, typically.
The ideal RPM range depends on your engine, and the speed depends on your transmission gear ratios, rear end gear ratio, and tire revolutions per mile.
a