Forum Discussion
ShinerBock
Oct 20, 2020Explorer
4x4ord wrote:
Unless the Ram/Cummins engineers are idiots which I am certain they are not your transmission will do better at selecting the appropriate gear for fuel economy than you can. I just did a quick search to see what Cummins says about running the 6.7 at 1800 rpm:
Here
I never said they were idiots. They just don't have all of the data and computing power to know how am using my truck at the moment. They can only make a vanilla tune that will be okay for most situations. They don't know the terrain I will be driving in, the weight I will be carrying and so on.
Making a custom transmission tune based on different weights, grades, and driving conditions would take A LOT of computing power and space which would likely increase the cost exponentially. This is probably the reason why Ford and Ram give you the ability to take out gears since you know how much weight you are carrying and what kind of terrain you will be towing in, not them.
And Cummins is correct, between 1,300 and 1,500 is the sweet spot unloaded or requiring a light load from the engine. However, as engine load increases, that sweet spot changes.
![](https://i.postimg.cc/FzKcGGkJ/ISB-BSFC-NM-inserted.png)
About Travel Trailer Group
44,030 PostsLatest Activity: Feb 06, 2025