new ScangaugeD for big trucks

There are minor programming differences. The KR averages "instant" mpg readings over 8 seconds. The slowest sample rate on the D is 4 seconds (default of 2). The KR also has the ability to display instant profit/loss readings (per mile and/or per hour) once you enter fuel cost per gallon and revenue per mile in the "fillup" menu. The D does not have that feature.

On the other hand, the D can store info for 5 trips, the KR only 2 (probably because the KR uses that memory to calculate cumulative profit/loss for those A & B trips)


I have the KR and I'd probably just buy the D next time. The instant mpg readings still bounce around too much on the KR, and the D version has a cost per mile gauge so you could calcuIate instantaneous profit in your head if needed.

But if your revenue is less than ~$1.60/mile, that hourly profit gauge may come in handy because you'll find that different speeds are most profitable depending on load & terrain. Above $1.60, you'll probably find hourly rate is highest at/above the speed limit.

 

Why would you want the instant mpg readout to display over a longer period of time. That defeats the whole purpose. If you want to see your average mpg, select the average function. When you drive for economy, you want an instantaneous readout, not a readout 1/8th of mile later.

I do not use cruise control, 100% pedal control for me. I can instantly see my performance and adjust my pedal accordingly. I have increased my mpg almost .75 mpg by turning off the cruise control and I attribute all that to working the pedal constantly adjusting for "little" hills, wind, etc.

My worst trip is 7.92 mpg and am usually in the 8.7 mpg or more on all my loads with this method. I haul close to 80,0000 lbs gross and travel all over the country, including tons of mountains.

 

I didn't explain very well -- the readout is still updated every tenth of a second or so, it is just based on data averaged over the last 8 seconds. That should make the reading smoother than averaging over 4 seconds.

But I still found my instant readings would bounce around up to 3 tenths of mpg on a flat road. That makes it hard to experiment with stuff that is in the 1 tenth range.

The Avg mpg is just the running total since turning on the truck -- by the end of the day you could drive in 9th gear for a mile and still not change that reading -- so it isn't very useful for short-term fine detail experimenting.


It could be that these bouncy readings were aggravated by the crazy EGR swings on the Maxxforce. I'll get a chance to use the scangauge on a detroit 12.7 later this week and see if it is any better.