X15 questions

[Ricky]

(01-05-2021 )Rawze Wrote:  

(01-05-2021 )Ricky Wrote:  I need to start by saying that I'm not judging anyone. But I have to ask does anyone know how this particular X15 is one year later. Being that they wanted it turned up so high and seems like it was ran pretty hard. I'm just curious if anyone knows about it.

the guy will be lucky to get 400k miles out of it before it needs $25,000 worth of work done ti it... Truck will not make it much longer before it starts falling apart too... gotta love those super-truckers! (Stupid-Truckers!).

You sir are 100% right on that. I was just wondering if it even stayed together or if it's a paper weight. I didn't understand why they wanted it turned up so high to pull tankers. I used to live in western PA and those B trains run really high hp older cats and Cummins. But I have seen were they are running 120 thousand pounds of coils on the floor all the time.

[Camstyn]

I have a 565/2050 in a 2020 Pete 389, 260 wheelbase with 78” midroof, 3.73 rears pulling light van loads (courier freight, licensed for 55,000lbs but most miles are near empty)

Lifetime average is 6.3, 6.0 on winter fuel and 6.6 on summer fuel. Tried turning it down to 505/1850 but it gets the same MPG as factory setting, and drives the same, just less power on reserve at the end of the pedal which it never gets anyways.

Curious if anyone knows if the 500/1850 Efficiency actually gets significantly better economy than the performance when driven the same way. I did my linehaul run with a rental International LT day cab last week which has a 525/1850 performance series and it was way better than mine in fuel, like almost 20%. I know aerodynamics play a small factor (keep in mind I don’t drive faster than 57mph and this was a day cab), I’m a little baffled as to why it was so much better on fuel than mine. Tare weight is lighter and it had slightly better rolling resistance tires but same winter type treads. Rear end ratio and transmission same as mine.

I’ll be buying a new truck in the next year or so and this was a bit of an eye opener for me. A 20% fuel savings would be significant. I can do this run with a day cab if I want to.

You might be asking why I bought a truck like this to do this job. Resale value. The truck it replaced was an aero 579 with Paccar MX13 @ 500/1850 and it was no better on fuel than this truck, and I could barely give it away when I was trying to sell it.

[Rawze]

(01-20-2021 )Camstyn Wrote:  ...
You might be asking why I bought a truck like this to do this job. Resale value. The truck it replaced was an aero 579 with Paccar MX13 @ 500/1850 and it was no better on fuel than this truck, and I could barely give it away when I was trying to sell it.

(just putting this here for perspective) ...

Resale value means absolutely nothing if you spend $8,000-$15,000 every year in extra fuel. Someone has gained nothing whatsoever in resale value compered to the tens of thousands in lost revenue. this is especially if someone is running competitive market freight (dry/reefer/flatbed) and can use an aero spec'd for all fuel mileage instead.


I can literally take your loads at those weights and easily run them in the high 8's and low to mid 9's in mpg with my prostar (set at 475HP,1730trq/3.55 rears) at those speeds you mentioned and take home nearly 1.5x the pay every week, have half the maint costs, and even do it after undercutting your bid and stealing your customers away from you (just making a point, not trying to be sarcastic). - Your earlier question is why it would be so different ... so Yeah, that front end is literally that bad on those trucks compared to a full-out aero prostar or cascadia.

I Don't know about any one else out there, but I am a strong proponent against giving my profits to big-oil ... they are already rich .. I am not.

Instead, I make strong efforts to keep as much of that fuel money as absolutely possible. That is the smartest thing an O/O can do and makes the most business sense above all else because fuel is literally the number one expense in ALL trucking operations .. even in my operation where mpg is maximized.

(just generalizing here)...

Trucking is all about operating expenses, not profit margins. Anyone that would tell you otherwise is a fool. ... Sure, you might get a nice rate for a load here and there.. or a nice gig for a while that pays well ... but overall in our industry, trucking literally has absolutely the lowest average profit margin of any other industry that exists out there. This is because it is so competitive and awash with mega-fleets and over-burdened with O/O's who are desperate due to piss-poor management skills that will under-cut anyone just for scraping out a few dollars.


I would think that any level-headed business minded individual would start their business and equipment planning by focusing the hardest on the biggest expenses .. but it seems like how someone feels and what they want to look like going down the roads, how much HP and chrome, etc... .. or what only a salesman would tell you ... this brainwashing quote of "how much resale it has" -- like the typical used car salesman would say .. gets into their head and clouds their judgment straight in the opposite direction towards doing anything positive towards their biggest operating expenses.

This stuff gets into their heads and mucks any wise choices all up.. then they wonder why they struggle to save money, struggle to make payments, or struggle to pay for unexpected repairs, etc. - This especially considering most of us are competing with mega-fleets and low-rent rates. I literally could care less what the manufactured body-style of truck looks like, I want the competitive profit margin, not the looks or resale value. Anything less and it would simply drive me crazy knowing that I was giving my money away to some already rich oil company simply because of the vehicles exterior design. I would feel that I cheated myself every time I got behind the wheel.


(again, just generalizing to show how bad it the wrong equipment for a job can be)...

At 6mpg ~ 120k miles @ roughly $2.50.gallon = $50,000 in one year alone is fuel costs.

My prostar running the same exact loads, same routes, etc...
at 8.7mpg (what I would realistically get on the loads you mentioned) ~ 120k miles @ same $2.50.gallon = $34,480 in same year.

(and if there is any doubters on what I actually get for fuel mileage... here is the first million miles of fuel receipts ... ref: http://rawze.com/forums/showthread.php?t...8#pid24378 ) My fuel mileage is higher now than it was the first mil, and still inching upwards into the 8.6~8.7 range at this point now that it has 1.4 mil on the odo.

THAT IS AS MUCH AS $15,000 IN FUEL SAVING ALONE!!@!! IN ONLY ONE YEAR --- THAT IS $45,000 DOLLARS IN 3 YEARS ... AND THAT IS $150,000 DOLLARS SAVINGS IN FUEL ALONE IN 10 YEARS / 1.2 MILLION MILES - A FULL LIFETIME FOR THE TRUCK... I CAN BUY A SECOND WHOLE BRAND NEW REPLACEMENT TRUCK IN THAT SAME TIME JUST ON WHAT A NON-AERO TRUCK LOOSES IN FUEL ALONE!.

The IRONY is that what I do can absolutely be repeated... i am not a unicorn, there are plenty of other O/O's on this forum who have done, and can do the same.

I started my career with fuel at $4.00 gallon and the industry was still trying to adopt surcharge into their rates. Imagine how fast someone with a square-nose would go out of business trying to run dry-van with $4.00/gal and no sur-charge.

And then there is me ... I literally smile all the way to the bank every time fuel prices spike up because the surcharge rates that are now in place for trucking operations is based in the 6 mpg range. I GET 9 freggin' MPG, NOT 6! --> I literally make a higher profit when fuel prices go way up. That is a very good place to be in our volatile industry. I have set myself up so that I Don't have to worry about fuel prices, not one damnned iota. I have managed to turn a truckers number one operating expense into a profit margin of its own simply because of industry standard FSC (fuel sur-charge) rates. Because of this, I also now have direct control of fuel based expense/profits. They are in my own hands and not some rich oil companies who wants to jack the prices up. - That is the place to be in our lower than normal economy of trucking. I MANAGE FUEL EFFICIENCY NOW .. and not concern myself about fuel prices. Since fuel efficiency is in my own hands, I can manage it myself (keeping it well above the industry standard) instead of having to concern my operations on what the fuel prices are at any given moment.

[Rawze]

(01-20-2021 )Camstyn Wrote:  ...
The truck it replaced was an aero 579
...

Maybe I should mention that not all aero trucks are created equal either. There is a clear hierarchy of efficiency that needs to be considered all on its own. The differences can save or cost someone thousands a year in fuel as well, regardless of other specs. Here is an old post from 2016 that is a bit dated but discusses this...

http://rawze.com/forums/showthread.php?t...90#pid1990

And then there is rears, tires vs. weights hauled, tranny and engine specs, how its driven, how the egine is set up, any custom programming ti increase efficiency, and a whole lot more to the story of fuel and other operating cost savings.

[Camstyn]

Thanks for the well written response. I do need to clarify a few things just to help understand the requirements of my work and what you can and cannot get away with.

. My linehaul route is 625 miles per night, 5 nights per week, with eight warehouse stops en route. It’s in the south central interior of BC, so terrain is much like western Colorado. Every night includes crossing six mountain passes, seven brake checks, etc etc. It’s a lot of steep up and down and extremely twisty secondary highways. It’s nothing like interstate driving.

Due to this, there’s a fine line between driving for fuel economy and being able to complete your trips legally. You also need to run aggressive traction tires with a lot of siping, and a truck with 4 way lockers. You can’t skimp here and spec for efficiency.

Having a set back front axle comes with the penalty of eating up steer tires on these twisty roads, too. I go through a set every 90,000 miles on my 389. They had to get changed every 55-60 on my 579. This is using Michelin XZE2’s, which last way longer than anything else I’ve tried.

I also have to run a moose bumper on my truck. In 11 years I’ve hit at least 50 deer and 2 elk on this route. It’s unavoidable, I’ve probably had more run into the side of the truck than I’ve caught with the front. So there’s another strike against an aero front end, an aero truck with a moose bumper is still better than a 389 but it has to close the gap a little.

My business model is to rotate a new truck every 2.5 - 3 years, with resale value and less headaches/repairs and everything is under warranty. Selling this truck with 400,000 miles on it I will get $50,000 more for it than an aero truck, that’s just the way the local market seems to be here. The truck gets well maintained but I’d like to see it gone before the aftertreatment issues start to cause headaches. I’m not interested in playing mechanic, I have a pretty good work/life balance and I’m not willing to give that up. I want to deal with as little truck stuff as possible on my days off.

With all that being said, my four year long aero truck experiment was a flop. Any minimal fuel savings I experienced were only a small fraction of the money I lost in resale value. In a nutshell, that’s why I’m back to driving a truck shaped like a brick again this time around. I really don’t see 9mpg being possible. I’d love to be proven wrong. If I could spec a truck that would average 7.5+ however, I would not even consider resale value.

With all that being said, driving that day cab for one trip was an eye opener. After my 579 experience I didn’t think I was missing out on much by driving these bricks. I’m leaving money on the table. I’d love to spec a 7.5 - 8mpg truck. I don’t care about driving a “large car” I’m only doing it because from a business standpoint it’s more profitable than my 579 was.

I’m not making excuses, getting defensive or being argumentative, I appreciate the non candy-coated advise. Just wanted to explain how I got here.

[JimT]

Only things that jump out at me are the size/wheelbase. Daycab will be a little lighter then a sleeper. If you can run a daycab then you're looking at about 150-160" for a single axle (which sounds doable with your weight) and about 185" for a tandem axle. You combine good aero up front, a shorter wheelbase and a small gap between the cab (with full roof fairing) and trailer and you can probably gain about 1mpg. maybe more if you switch from a tandem to a single axle. (not sure what you have or if it's doable for you).

As for the engine, there could a some fine tuning that might help. Besides the tune there could be a few physical differences between your engine and the one in the rental that might contribute (speculation on my part). Also, check for boost leaks, EGR tuneup, exhaust leaks.

Then there's the rest of the driveline. You didn't mention specs for the rental so it's hard to compare. I was having a chat with a friend the other day about speed and fuel mileage. He noted that sometimes he can get better fuel mileage by driving faster then 62mph. I pointed out that the engine RPM can play a big role. Depending on your rear end and trans gear ratio's you may find that slightly faster speeds or a different gear yield different results. I for one found that in my truck 63mph in 13th gear was better then 62mph, but in 12th gear 62mph was better. Also, again in my truck, 1350, 1450, and 1550 rpms are sweet spots. Even as little as +/- 10 rpm and I can see a difference in fuel usage. (based on repeated testing with cruise control set with same weights and roads). My truck does good in 12th and 13th gear, but if I drop below 12th gear (direct) then I see slightly lower fuel mileage. There's a chance that your truck might perform better at a slightly higher speed, like 58mph or something else up to about 62-63mph.

Finally there's driving style. You sound like you have a handle on that part and I'm getting too tired to type much more. But for others reading this, driving style or habits are probably one of the biggest contributing factors to good or bad fuel mileage. Keeping boost levels down, letting it gain speed downhill (with tranny out of gear if conditions permit) and letting yourself slow down a bit going up the hills. There's plenty more to driving style, but you probably get the idea.

[JimT]

Oh, and while I don't know the market in BC, down here in the states daycabs seem to hold their value for a lot longer than a sleeper. Maybe due to the abundance of sleepers sold around 400,000-500,000 mi as opposed to many daycabs being kept by fleets to closer to a million miles (at least in the LTL world which is the largest market for daycabs)

[Camstyn]

Thanks for the feedback. I don’t think I could get away with a single axle tractor, I need all the traction I can get. An aero day cab may be in my future though, I’ll have to rent one again for more than one trip to verify the results that I found.

I guess my biggest question is since I get the same MPG’s at 565/2050 and 505/1850 with my performance series, would I see better numbers with an efficiency series at 500/1850, all else being equal? I’m not using all of it anyways so I wonder if there is anything hidden in the differences between the two engines that would actually net me better results, or if it would just be the same with less power on tap in reserve. I would normally assume so but was surprised how efficient my rental with the performance series at 525/1850 was. It was not full aero but did have cab and roof fairings, and 46k rear axles. Heavy haul truck. I could spec a similar truck with regular 40’s, weed burner exhaust, disk brakes, lower chassis side fairings etc to make it lighter and more aero yet.

Has anyone experimented with both a performance and efficiency series doing the same job to see if the efficiency is actually more efficient, or if it’s just slower?

[Rawze]

(01-21-2021 )Camstyn Wrote:  ...


I guess my biggest question is since I get the same MPG’s at 565/2050 and 505/1850 with my performance series, would I see better numbers with an efficiency series at 500/1850, all else being equal?
...

Work performed is the result of fuel consumed.

YOUR RIGHT FOOT and how hard you push your equipment is what directly determines how much overall work your truck is doing and therefore its fuel consumption.

You seem to have this misnomer in your head that one engine is significantly better with power vs fuel used than another under the same exact amount of use .. and this is mostly not true. There are slight differences but they are not going to make any significant differences due to demands like your describing.

WHAT overall power and torque you apply on demand from your equipment to the work load determines the amount of fuel you used, plain and simple. ALL of those model engines are going to be very similar if you drove them using the the same exact acceleration rates and speeds, weights, etc. and use from them.

LEARN TO DRIVE BY A BOOST GAUGE AND TO SAVE FUEL FIRST AND FOREMOST and you will save money in fuel and maintenance above all else.

START by learning how to climb all the hills and such and never let the boost go above about 20 psi... FIND BETTER GEARS and keep RPM up instead of using high torque and everything will benefit form this far more than comparing the nuances of one slight engine variation or another against each other.

If I flashed my ECM with a "performance tune" and drove my truck as hard and with as much HP and torque as you claim that your demanding from yours... I would only ever get 6 mpg too!