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How you "shift" an 18 speed, manual shift, transmission. This transmission shifts by the driver manually moving the shift lever and also by the driver moving a high / low range control switch mounted on the shift lever as well as a direct ratio / overdrive ratio control, also mounted on the shift lever. The high/low and the direct/overdrive shifts are done by air pressure using the vehicles compressed air system. If you have no experience with a manual transmission, the following will most likely seem as if it were written in a different language... one you don't speak, but you should understand this if you have truck driving experience with a manual trans. that had a range shift, or if you have driven a truck with a two speed rear axle. If you are familiar with a 13 speed trans, you shift the 18 speed the same, only with the 18 speed, you can "split" the lo range gears also. If you are not familiar with that... The 18 speed Fuller Roadranger has a 5 speed and reverse "H" shift pattern, (with neutral being in the "middle") that you repeat twice. The pattern, on left hand drive trucks, would be, starting in low range direct, low, or creeper gear, which is over to you and down, followed by first gear, up over and up, second , straight down, third, again up over and up, and fourth, straight down. Each one of these stick positions in low and then again in high range, can be "split" in direct ratio and overdrive ratio. In other words, you can get two shifts in each shift lever position, so if you are counting you start with the transmission in low range, the splitter in direct put the shifter in low gear position and get two shifts using the splitter, gears 1-2. You would make the 1-2 shift by moving the splitter button from direct to overdrive, not the stick. When you are ready for the next upshift, move the shift lever out of the low gear position to first gear position, and just before you accelerate, flip the splitter back to direct and you get gears 3-4, move shift lever again split 5-6, move lever split 7-8, move lever split 9-10. Now you have reached the last shift in low range and you repeat the shift pattern by shifting into high range moving the shift lever out of the 10th. gear position and passing through neutral and going back into first gear's spot, only now you are in high range, and you will go into 11th gear by pulling the splitter button back into direct as soon as shift lever has been put into the "first" gear spot...split 11-12, move lever split 13- 14, move lever split 15-16, move lever into the "Big Hole" and split 17- 18. There. Simple as pie, wasn't it? And the government considers all this "unskilled labor." HA! I'd like to see a politician shift an 18 speed.
Having 18 speeds does not mean you have to use all 18 speeds, or whatever amount of gears a particular transmission you may be driving would have, it depends on the load and terrain what gear you need to start from a stop in, as well as which ones you can skip depending on the load, your speed, the terrain etc.
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