Increasing Speed Before Hill Climb for MPG’s?

I'll make a case where I had a '87 COE from freightliner with a Cummins big cam. At 80000 flatbed going up breezewood via I-70 Townhill is a 5 mile pull more or less. The COE will run that in 4th high or 5th low at around 18 mph give or take 3 exactly depending on air temperature and humidity. If it's cooler or cold, she'll do it at 22.

That takes time.

My company at the time DM Bowman handed me a virgin Mack Daycab with their new 350 and new model production roughly the mid 90's time period. We could run Townhill at almost 45 upgrade. THAT was worth the savings in time which now makes it possible to gain 15 minutes or so wriggle room against Fishertown PA which is also sitting on top of Babcock Ridge, itself almost a two mile pull with a 10 mph 220 degree switch back at the bottom on PA 56 from Altoona-Bedford area of the TPike. In this case the Mack did better due to short gearing and short legs on the transmission plus a modern early generation computer engine which still put out 350 or so roughly. But performance versus a airbreathing 400 cummins was quite the difference.

I do miss that particular COE, it was a reliable tractor for the time I had it until it was sold. The company monitored driving using Tripmaster and they can tell where you are shifting at and determine if you are idling at a stop light too much by percentage as well as overspeed which company limit was 55. Not a problem in flatbed, but a BIG problem in regional van in the south when everyone was doing 70+ blasting by you, the traffic accident waiting to happen. And this was before the days of 61-63 mph governed trucks running in 75-85 states years later.

Another time in PA south of Williamsport on the upgrade to Summit, is a platform scale west of the river. I was 81200 gross due to too many pallets in the nose and pulling that one at 16 or so holding up a state trooper. Because I was well known on that route coming through sometimes twice daily the trooper figures I was heavy. Whips around me, opens the scale in my face on the left and bingo 81200. I had a little '83 COE with maybe a 289 ro 300, I forget exactly. It's not much of a engine. I usually pulled that one at 21 or so.

From that day forward I discovered I could cross over at the Sunbury Dam and run the 180 route on the flat ground east of the river right into Williamsport at high speed. That was what improved the fuel burn for sure.

 

Old iron had a redline of 2300. You did not "Wake up" those engines until about 1400-1500 to 1850 or so. Anything over that to 2300 was pure speed if your road was flat enough to let you do it.

You could get into above 1900 towards 2100ish 2300 lightly upgrade to get there if you are short on time for delivery however you kept a eye on Mr Pyrometer, a gauge that usually read 1200 upgrade at the exhaust manifold but would at times let you run up to 1450 or so for a maximum of 5 minutes. No more than that. That's in degrees. Your turbo will be red hot towards orange and maybe the manifold and pistons are steel if you are lucky ceramic. If it's aluminum anything, you are good to 900 more than that you are pushing the metal too hard.

 

X1Heavy really likes to talk about climbing hills. If you don't believe me just wait......

 

And why not? It's a favorite activity in trucking. The steeper and crooked the better. Cabbage comes to mind.

I don't consider pulling mountains a problem. We will get over any day. It's the getting down that separates the wise from the stupid. I never worked a day in trucking for part of that reason. It's fun.

My first year and going across WVa in my first winter was all about snow and ice in the passes one by one at a time. All of them have to be run no matter how deep or bad it got. We had a awesome truck in those days to do it being dedicated to GM Auto in Baltimore. (Lexington Ky, Glass for Astro vans with curtianside)

My trainer pretty much gave me everything he thought I needed and got to sleep while it's my turn to pull those hills with many more to come. ice, snow back to ice then rain in the hollow and back to ice then snow etc. All night. We be in Ky come morning to get loaded.

 

I run the cruise all the time. Love cruise. I set it to drive down the driveway to the mailbox in my personal truck .

Lately I drive the exact speed limit to keep my company happy and they reward us for it.

Kick the cruise off by tapping on the clutch pedal on really steep grades so the Jake can maintain.

Small grades I let the truck get up to 5 mph over without kicking off the cruise and at the apex of the valley I mash the pedal and build boost and climb out.

Don’t care about mpg just keeping that engine breathing especially during the heat of the summer