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[Chance]

Originally Posted by The_Breeze

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All this is just my experience with the V10, which is part of why I cited it should go. When I hit a 2% grade on CC and she drops 2mph then downshifts, that's absolutely insane in my book. I'd gladly give up 5mph before she even thought about downshifting. I'm not dropping $500 on on a 5 star to fix it. That's insane.

All just JMHO.

What you have experienced with V10 is a common issue with many naturally aspirated engines unless they have some form of variable displacement, like a V8 running on 4 cylinders. And that technology isn’t very effective in large trucks and motorhomes anyway, so not a “viable” solution for what you described. It’s not a V10 issue in that it frequently also happens with V8s and V6s. It’s all caused by need to save gas as much as possible.

The problem most drivers don’t understand is extremely predictable with simple math. Some engineers get it, but drivers don’t like it, so they try to “fix” the problem with software. And most of the time it’s not a fix because it’s not broken; it works the best way even if drivers don’t appreciate it.

Example: The engine in a large motorhome or equal-size truck that gets around 8 MPG may be making around 100 HP depending on speed, and if spinning in range of 2,250 RPM like a Class C similar to yours, is working at around 60% of available torque. That’s a selected compromise to save fuel while providing reasonable drivability.

When you encounter a 2% grade, power requirement suddenly could go from 100 to 150 HP, and if RPM is kept the same at 2,250, torque would jump from 60% to 90% of available, which isn’t ideal for fuel economy or engine wear. It’s better for motorhome to downshift from 6th to 5th to increase RPM and reduce torque below 90%.

It’s possible to reprogram software to force transmission to stay in 6th gear and make engine work at near-maximum available torque, but what makes these guys think they are helping matters? Just because they achieve what they want doesn’t mean they made conditions better.