Nice video and great topic. I will throw my 2 cents in and see if we can help your subscriber. First off my back ground. I’m a retired owner operator that had specialized in time sensitive and temperature controlled transport to and from Alaska year round.
I will use my 2013 Western Star 4900EX as a comparison truck. Truck specs: DD 16 600hp 1850 ft/lbs 18 speed and 3:25 gears. In my operation that truck averaged 5.5 mpg over 370, 000 miles.
I’m a numbers guy and watched fuel economy on every trip since that was my biggest expense.
I worked with Bully Dog and I ran a 20% tune. Truck was run on chassis dyno at Western Star dealership with and without tune. Stock was 525hp to the rear wheels and 649hp with the tune. 1850 went to 2400 ft/lbs. I gained .5 mpg in my operation, but I was always the slowest truck up the hill. I drove for fuel economy. Tuner and dyno $4000. Fuel savings $7000-10000 Dollars per year depending on fuel cost.
My recommendation is get all service up to date, run over head and make sure no charge air cooler leaks exist. Then get an APU and shut main engine down when parked. Install block heater and oil pan heater and run those of the APU to keep engine warm. Also the Carrier APU was plumbed in the cooling system to circulate coolant through truck engine. I did that in Alaska and would shut my engine down to negative 25 at night. When I started the main it would show 100 degree coolant temperature and drop to about 70 after moving coolant through the engine. I also used a Webasto Diesel heater to supplement the heater of the APU to keep the 82” sleeper warm.
The subscriber runs in the worst conditions and the only way to save fuel is to shut the truck engine down. Also winter fuel will probably cost him at least .5 mpg in fuel economy. I used to drop .8-1.0mpg in the wintertime due to open lug traction tires and winter fuel.
I hope this helps and all makes sense. Good luck and keep the shiny side up.
cullenmiller
Thank you for picking my question on your channel Josh. Love the math break down and knowledge you shared on this. Also thank you to all the other people who commented on this. I'll be doing more digging and will update with what I do. Thank you again Josh for all your knowledge on Cat engines and teaching!!
lmac
We did that calculation in the 70s during the fuel crisis with regards to a school buss and a Datsun. But instead of weight we looked at how many students each could move per gallon.
LeewardStudios
In South Africa back in the day before USA semis pulled out of our country between 2013 and 2016. We got the International 9800i with Cummins isx with 450 or 500hp and the Freightliner Argosy with options of Isx 500 or 530, Detroit 60s, and C15 before Cat pulled out of trucking industry all with eaton Autoshift 18 speed and 4.89 rear end.
Trucks here also pulling loads of 80 000 pounds in most intense terrain you can imagine. I have been to USA to drive semis and you cannot compare to here.
My father and I specialize in Cummins we have managed to tune up isx engines by doing overhead settings on injectors and engine brake and changing features and paramators on the ecm and on the transmission ecu. The result giving more it power to pull up the hills quicker and keeping shifts between 1500 - 2000 rpm. Where as before it was at 1000-1500rpm. Owners were getting better fuel milage and doing more loads because they were getting to there destination quicker.
Even though we don't have software for Detroit and Cat we could still change the transmission settings from economy to heavy haul application and that made quite a difference in shifting and pulling.
We did an experiment and took an ecm from an International 475 and went to cummins and told them it was from a freightliner and we asked them to uprate the power to 530. We then put the ecm back on the International and BOY did that move.
So the quicker you can get up the hill the less you engine has to work. That's what we have found here.
raymondwalton
Just from experience, when the c-15 went to sequential turbos and Acert, they lost mileage over the previous 3406e for example. Most were in the 4 mpg range for just average use which should have been 6ish. I think it had to do some with Cat trying to meet emissions standards and trying to get there without using EGR.
scubasteve
That is possibly the best answer to that question I've ever heard. As a Cummins Tech at a dealer myself I've found myself on the spot having to answer that loaded question. The best answer I could ever muster was leave your truck alone. Great information here hopefully more people will see this and stop asking.
elliotconger
I do this math for people all the time and so many people get all upset with me when I show them that a properly tunned non-emissions complaint 80, 000 truck is vastly more fuel efficient for the work actually being done.
Sad fact of reality is our common vehicles get horrible fuel mileage because it generates huge tax revenue for the government.
tcmtech
0:16 Want to improve your mileage... don't idle. Want to keep equipment warm... Espar heaters. You're not listening to the experienced guys in the field. You want the answer to be more power.
Failure_Is_An_Option
I used to run my 550 loaded heavy running local, light to light. Average 6 Mi to the gallon. It all has to do with the operator and right pedal. Keeper in the RPM range an easy on the throttle. That's it. I ran a Pete 379 with a 575 cat and averaged eight miles to the gallon with it. Pulling 30, 000 lbs. As long as you keep them on the north side of the torque curve it around 1450 rpms they're very fuel-efficient
dennisrichardville
The tuning I have seen improving HP and fuel economy did not considered the EPA limits. Having worked for a diesel engine manufacturer I know the pressure put on the engineering team to meet regulations…It all the time limit the maximum performance an engine can reach. Good video’s
gaetanbolduc
I'm from North Dakota myself. I'm guessing he is being hurt on fuel mileage by just what you said. Sitting and idling or high idling in below zero temps. Lots of low speed on gravel roads. Lots of stop and go (relatively speaking). Before he starts changing the tune or anything, he really needs to see what it does at, say 60 or 65 mph for at least a few hundred miles with little or no wind. Wind in North Dakota is a huge factor that can drastically affect fuel mileage.
guyconnell
The component missing is Break Mean Effective Pressure which effectively is a formula to compare how powerful and efficient an engine is whilst ignoring displacement and RPM.
My understanding is that these diesel tunes basically allow for a much leaner burn at medium engine loads which improves the BMEP. The reason they aren't like that from the factory is that it absolutely SKYROCKETS NOX formation. This was part of the dodgy tunes VW had on their diesels which made them perform really well and sip fuel. It was only possibly by not adhering to emission limits.
It seems that pre SCR commonrail engines are able to get the most out of these kinds of tunes because of their fine control of fueling and not having to worry about screwing with any adblu system.
You could theoretically do this with an SCR system but you'd have to either undermine the SCR system so that it doesn't break down all the NOX or tune the SCR to consume way more adblu.
SpencerHHO
Thanks for discussing this topic! I've got a first generation 250hp 3126 in my RV that I had pondered the upgrade to a higher HP rating and decided against it since it would take years before I would see the cost benefit versus leaving it alone. While it doesn't like to move down the road at much more than about 65mph, it will do it all day long and come back for more - which means more to me!
duanebuck
I have seen an increase in fuel economy by upping horsepower in a C-15 MBN powered log truck (lots of off road and adverse conditions). It was rated at 525hp stock. I took it to a guy who specializes in CAT engines and had him upload a CAT 700HP C16 tune. I was immediately able to climb hills at least two gears higher (18 speed) and it would climb like a boss at 1400-1600 RPM instead of having to rev it out to 1800-1900 (two or three gears lower) on the mountain passes. My EGTs were also much more manageable probably because I went from 28psi boost stock to 42psi post tune. The truck gained over .5 MPG. My understanding is that I was able to run the truck in a much more efficient RPM range regardless of the terrain (less total engine revolutions to overcome a particular hill). Horsepower is just torque multiplied by RPM so if you an run the engine at a lower rpm and make the same horsepower you had at a higher rpm previously you will be ahead. Hope that makes sense!
Gage
I had a 475 acert updated to 550 crappy mileage and power. Rerate was done with a platinum overhaul. 3.8-4.5mpg. Single turboed it and a custom 625 wheel hp tune and got 6.2mpg. Have ifta reports to verify the mpg.
timburton
Emissions compliance is not about saving the environment. It's about tax revenue to be had by making use burn more fuel to do less and spend more on BS that doesn't help make anything better in the long game.
The oil industry as a whole only makes about 15 to 20 cents per gallon off fuel it sells whereas the government gets multiple times that in tax and regulatory kickbacks from it from the well to your fuel tank. Big oil itself would love to sell us all half the fuel at twice the price because it would be great for the bottom line.
The problem is that big government won't have it due to the lost tax revenue. This is why big oil gets billions in government kickbacks to keep them happy and not rock the taxation boat.
tcmtech
Josh, I was an engineer who used to tune engines for an OEM. Mostly gasoline engines but dabbled in diesels some. I'd make a couple comments. First, you're right that by increasing horsepower by itself you wouldn't get better mileage. It comes down various aspects of the tune, especially injection timing (which impacts the engine similar to ignition timing on a normal gasoline car). You can see significant benefits from that, but it'll also increase combustion temperatures and pressures which can have negative impacts.
However, one of the other things that injection timing impacts is emissions - and even on the engines that were pre-DEF, pre-DPF, pre-EGR (take your pick), there was still a period with some level of NOx requirements (highly tied to combustion temperatures) and there were some aspects of the tune related to that.
If you'd be interested in doing a collaboration video talking about efficiency (I've spent a good sum of effort improving my 3126) I'd be glad to.
TedsGarage
One thing that may help him to reduce fuel usage is a heater to keep the coolant temp warm so you do not need to keep idling. Artic Fox is one I have seen used, it will heat the coolant and pump it through the engine so you can keep the engine warm and heat the cabin using less fuel than idling does. They are not cheap and it would take a while to see the savings but not idling your engine for hours a day is a big benefit not just in fuel savings. A horse power boost and torque increase could get him in a higher gear but it will hard on the drive train if driving conditions are rough. Thanks for the video Josh.
badgerpa
I'm a retired Engineer who back in the 60's and 70's used to follow racing until it all the cars basically became identical. So I switched over to watching efficiency competition to see what ideas people have. The Shell eco-marathon is probably the most noted of efficiency competitions and there are some trends that are not practical for everyday but are interesting. This is really designed for College, Technical Schools and High Schools with small budgets. Most entries highly modify a very small engine with ball bearing cranks and electrically pulse oil spray to the bearings much like a turbine and the fuel injection pressure is as high as possible. Anything to remove "parasitic energy use". These guys will get like 4, 000 mpg but like you show the vehicles are extremely minimal and light weight. The University of Nebraska used to test farm tractors and rated them with Horse Power Hours / Gallon. The old John Deere long stroke two cylinder diesels had the highest value at like 18 horsepower hours per gallon. There are some Caterpillar crawlers in this competition but this was many years ago. Maybe Caterpillar Corporate should submit an entry into the Shell eco-marathon (mainly for advertisement and to attract gear head type Engineering Students). 🤨
jeffsnider
I had a local semi-retired cat mechanic re rate my 2000 Peterbilt C15 to 600 from stock 550. The truck had just nicely been broken in after complete over haul. Now I only have 20000 miles on it so far but WOW did that ever wake that truck the F up. It feels like it pulls twice as hard . Single turbo boosting to 40-45 lbs. Not sure 😕 it helped milage but wouldn't consider going back to the way it was .
Oh and I'm regularly pulling 138000 lbs . 62500 kgs
