Power or Speed

My truck has 455 hp and is a 9-speed. These are the specs from Stevens Transport out of Dallas, TX. I think they’re the 5th largest refrigerated fleet in the US. Most of their loads are heavy. Their older trucks in the early 2010s (and possibly even before) were 10-speeds. They eventually switched to 9-speed, but now I don’t know what they use for their automated transmissions.

I drive OTR, and in most cases, I will only downshift twice going through steep uphills. It is rare to downshift three times.

9th gear = 52+ mph
8th = 38-52
7th = 27-38
6th = 18-27

The key to minimal downshifting is to keep records of all uphills across the country. This not only saves time, but can also increase your fuel economy as you will be on higher gears through most of the upgrade. This is what you want to take notes on:

• State
• Highways type and direction
• Gross weight
• Mile marker to the nearest quarter (0.25) when you should begin accelerating, or mile marker where the upgrade begins.
• Mile marker when upgrade ends.
• Speed you need to be traveling at the start of the upgrade. Ideally, you want to accelerate gradually.
• RPM you need to downshift for every gear. For example, on a steep upgrade, 1150, 1150, and 950 RPM, which applies to 9th, 8th, and 7th gears, in that order.

There is more to that, but that should get you started. If you do this, you don’t need more hp.