Double Yellow's Company Driver to Independent Thread

kr has been talking about cruise more then foot these days.

holding the cruise down is the same thing as the foot. i don't see how it can improve mileage. so why put cramps in your foot. holding that pedal down 11 hours. going slow, going fast, going slow, going fast. you go up you push the pedal down, you go down the pedal comes up. just like the cruise.

the rest of us would appreciate you just using the D--- cruise. and driving the truck. and stop playing your stupid games just becuase your suddenly getting passed. you got the speed. then GO. you got the power, then CLIMB. and be gone.

 

Not from my experience. The problem with cruise control on rolling terrain is that it is programmed to keep you at a fixed minimum speed. When topping a hill BELOW that speed it will continue with maximum throttle until the speed is achieved, in spite of the fact that had it simply been PATIENT and allowed the upcoming downhill to hit that speed by coasting you would have saved that fuel.

"Dumb" cruise control can't anticipate uphills, either. If you want best fuel economy you would give about 50% boost just before reaching the bottom of a downhill in rolling hills, then hold boost at about 50% on the climb, downshifting as necessary to keep at or below 50% boost. DY seems to be monitoring horsepower, which seems to be the same thing in the long run (my own experience was using a boost gauge).

Fuel savings can be pretty dramatic. My own testing on the run between OKC and St. Louis with a fairly heavy load showed fuel economy shot from just over 4 mpg to almost 7 mpg in an '03 KW T2000 by backing off on the "gotta hammer down" philosophy of pulling hills.

My own experience with cruise control vs "free footing" is that CC will be more fuel efficient on flat terrain, while I can free foot more efficiently on hills and rolling terrain. Although I understand there is a more intelligent cruise control available that uses GPS and terrain mapping to do the same thing I do when free footing.

 

Depends on suspension of truck, too. Macks (2012 or newer) I am driving now are easy to foot control and automatic transmission. There's a '$$' indicator on the dash that tells you your fuel mileage is optimal. Goes away climbing hills.

The million-mile International Eagle (2005) that I drove Indiana to Prairie du Chien (WI) turns was very, very difficult. Too bouncy to control speed evenly and well with your foot so I always used cruise if weather permitted. Standard 10-speed. Southwestern Wisconsin's very hilly. Cruise goes away when free-footing, necessary in the hills anyway and back on cruise ASAP.

Think Bright One has a similar vintage Eagle, maybe better suspension...

Dunno.

 

Cruise gets you there with a lot less wear and tear on driver if an older truck and rough road. I-39's improved a lot this last year. I'll still take the cruise if just for driver comfort. Uh, that's me...

I think Blu would point out that cruise, like automatic tranny, is blind, though. Bright One's not blind and VERY motivated.

 

Yep I would point that out.

And also that the next generation of Cruise they plan to hook to GPS info so they can spool up a bit at the bottom and back out a bit before the crest and use gravity to accelerate on the down hill.

One of my plans for the weekend is to see if I can get the ECM set to only allow 20 pounds of boost while on cruise but allow full boost on the peddle. With the Auto it will downshift on its own and never peak the turbo while climbing the hill. Should help train me better, cause I would rather watch out for 4 wheelers doing stupid things than bird dog a gauge. Figure it will save a good chunk of the fuel I wast now rolling across I40/I44......

 

With cruise being controlled by even a comparatively simple chip that's calculating at millions of flops per second, while free-footing we're functioning at intervals of full seconds or at best large, partial seconds, the cruise has to be infinitely smoother until it kicks down, like when I start up my hill. Until then, the cruise will run circles around my unsteady foot and save fuel driving up from Spencer, for example, which is hilly. But Dean Hill causes the engine/tranny to kick down and drink fuel.

If I prevent that with my foot, I save fuel.

The big issue in fuel usage is speed and/or grade. Grade is still speed, speed up a grade. Uses fuel faster, of course. Faster uses fuel faster. Blu, playing with your boost sounds very techie.

The pivot points have to do with cost of fuel, fuel usage and revenue per mile. The Haz outfit I drove for cared not about fuel. Get that truck back for another load, please. Mine was ungoverned, most of the others were governed at 71. Wanna idle, okay, idle. Get that next load, please.

Be interesting what drop in diesel does to FSC (Fuel Surcharge) which accounts for a large part of revenue for the megas. They all break out revenue and FSC revenue.

You can bet the brokers, shippers and the carriers will want to keep as much of the benefit for themselves, not pass it along to the O/Os, L/Os.

As usual, the game's rigged against the little guy unless the little guy has a niche of some sort.

 

first off there is a soft cruise or hard cruise that cab be programmed into the ecm. hard cruise tries to keep the truck at the exact speed setting and gives full power and ups boost in an attempt to accomplish this, soft cruise not so much so it allows for a drop in speed and a few mile an hour and thus less boost and fuel is applied.

and isn't hard to get used to doing it with your foot, its takes a bit but can be done, years ago when cruise was almost unheard in large trucks it was the norm. most just don't take the time to learn it. and since many quote kr, its the difference between a truck driver and a steering wheel holder.

and in spite of you not being able to think it can do so, taking off the cruise and driving with the foot can add .5 and up to the mpg.

 

Before we had cruise and ECMs, you drove 'as if you have an egg' underfoot.

That was how you improved mileage. Back in the day. Still holds, I'm sure.

All the same, today, I'm sure Bright One's foot is much more motivated than mine... more nuanced. For me, better mileage is nice, not much more. Company driver, home most nights.

And he's likely trying to weigh out the opportunity costs, etc. as well.

So he might go for mileage on today's average-paying load, or hurry and push harder to catch that high-dollar load tomorrow morning...

Not sure one size fits all.