Why do you Cummins guys want more gears
I’ve heard a number of Cummins fans saying they are waiting for an 8 or 10 speed transmission before getting a new truck. Why? Does the Cummins struggle to get your trailer moving from a stop? Or are ...
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Same reason why 18 speeds are better than 10 speeds in class 7-8 trucks. More gears give you more opportunities to be at the right rpm for power/efficiency at different driving speeds. When towing really heavy in a 10-speed semi going up hills, you are more limited on your speed because the large step down to the next gear may not put you in high enough rpm to make enough horsepower. In the same truck/engine towing heavy in an 18-speed, you are less limited since you have more gear options making the step to the next gear much less and therefore putting you at a better rpm to make enough horsepower for higher driving speeds.
It is just like the 6-speed F350 versus the 10-speed F350. Towing heavy up a hill with a 3.55 F350 6-speed, you may be limited to 55 mph in 3rd at 2,800 rpm because up shifting to 4th would put you down to 2,000 rpm where you are making much less horsepower. It may be too much of a step in this scenario and you start to lose speed every time you shift to 4th. Therefore you are limited to around 55-60 mph.
In the 10-speed, 5th gear is close to 3rd in the 6-speed and 7th gear is close to 4th in the 6-speed. This means that 6th in the 10-speed is right in the middle so instead of dropping 700 rpm in the 6-speed, you only drop 300 rpm in the 10-speed which puts at a higher rpm to make more power and are not as limited to certain speeds as you are with fewer gears.
It is just like the 6-speed F350 versus the 10-speed F350. Towing heavy up a hill with a 3.55 F350 6-speed, you may be limited to 55 mph in 3rd at 2,800 rpm because up shifting to 4th would put you down to 2,000 rpm where you are making much less horsepower. It may be too much of a step in this scenario and you start to lose speed every time you shift to 4th. Therefore you are limited to around 55-60 mph.
In the 10-speed, 5th gear is close to 3rd in the 6-speed and 7th gear is close to 4th in the 6-speed. This means that 6th in the 10-speed is right in the middle so instead of dropping 700 rpm in the 6-speed, you only drop 300 rpm in the 10-speed which puts at a higher rpm to make more power and are not as limited to certain speeds as you are with fewer gears.
