New International A26 12.4L Engine

Does anyone have mpg numbers on the A26 that runs the speed limit? We set our trucks @80 to 85 mph. And run lighter loads from west coast to upper Midwest and back. Thanks in advance.

 

I am very impressed with the A26, fuel mileage has been great. I don’t think trucks have any business doing 70+ mph but if you must run that way, I’d run any aero device you can get on your trucks and trailers. At those speeds, any aero device is going to have a fast payback. I’d gear the truck to run at 1175-1250 rpm in top gear so you have direct drive for when you have to drive in slower states or work zones. You’re going to have a hard time getting a dealer to spec you a truck to do 80+ mph. You’ll get much better fuel mileage if you’d run at 68 and a downsped drivetrain. I’d refuse to work for someone that expected me to drive that way.

 

Driving or rather cruising at 1250 rpm seems absolutely retarded unless you do not need any fuel or down a grade.
Engines and transmissions are not made to lubricate themselves at that low of a rpm. And seems like that would be lugging if going uphill loaded. And overheat likely shorten service life as well.
I'm not the engineer so I could be wrong.

 

It is the default spec on all the new trucks unless you don’t want a downsped drivetrain. All the new motors , transmissions, and axles are designed with downspeeding in mind. You couldn’t run a down sped spec with a manual. I suppose you could but you’d be changing between top gear and direct a lot. The automated boxes do it much better when running a downsped spec.

The new Mack/Volvo turbo compound motor recommends a cruising rpm of 1000-1100 rpm while everybody else is still recommending 1150. This guys’s spec is special in that he wants to run super fast.

 

So in your mind trucks have no business running the speed limit? Wow! With the advent of the ELD I enable my drivers to maximize their productivity by running the speed limit in EVERY state and that's wrong? Haha ok then. With the paccar/and Volvo we are averaging just shy of 7 mpg so I would be impressed if the A26 would get us close to 8 mpg. We have an O/O team with a Detroit that hovers in the 8 mpg range running the same speeds as our company trucks. But I've never had much luck with Freightliner. Guess I'll take the leap and try an International. Hell the price is definitely right!

 

There are a lot of problems with running a commercial vehicle at those speeds. I’ve posted in other areas my thoughts on speed and the fixation so many have on what the speed limit says. I don’t care if the limit is 90, I’ll drive 60 mph just like I do every day unless the limit says go slower.

The new LT is a huge improvement over the ProStar and the A26 has been doing great.

 

In some applications, like the live cargo we ship, the slower we go, the less net payload we can carry. So speed is needed.

On some routes, like ours, a driver can make two turns per 70 hour cycle if running the speed limit, or one and 3/4 running for optimum fuel. How much less can I pay a driver if he never does a 34 on the road? How much longer will the average driver tenure be? How much fuel and wear and tear on the truck does a 34 on the road accumulate? How much more revenue does the two turns per cycle truck produce for the same fixed costs? Back office overhead, driver benefits, truck insurance all remains fixed.

On some routes, like ours, running the speed limit means missing rush hour in two major cities, v.s. running smack into it. How much fuel does it take to cross Seattle in rush hour vs driving at speed?

Just some examples of why speed is just another variable. Yes, I replace drive tires at 200K; yes my brakes get replaced more often. Yes, fuel is higher. Among other issues. The question is, what is the NET.

 

Ran my fuel for the quarter and I got 8.63 mpg. I’d really like to get it closer to 9 but most of my loads are 72k and up with only a few lighter loads here and there in the 65-68k range and I’ve maybe done two loads that were around 58-60k this quarter, deadhead was 16% overall. I get my worst fuel mileage going across the turnpike in PA and when I have to run south from PA, MD, DE to NC, GA, SC, and AL. Especially when I’m leaving DE until I get past Richmond heading South.

 

My salesman gave me a workbook he received during the mobile training tour Navistar had about the A26. There are some neat things in there.

Mass Air Flow Sensor has no service interval, Paccar uses EGR Venturi sensor instead, with 80k mile service interval

Borg Warner uses Titanium compressor wheel instead of Aluminum, found in Holset products. Also features a roller-less design and eliminates a lot of moving parts

Standard cooling package whether you choose the A26 or X15, capable of cooling over 600hp.

Six blade fan and single cylinder air compressor. Standard with on/off fan clutch. I chose the viscous 2 speed clutch on mine. I wanted the Visctronic Clutch from Borg Warner but it wasn’t available yet.

Engine and after treatment ECM all one unit instead of two in previous design

Wiring harnesses are foamed in encapsulated.

Has “domed” pistons, similar to what Volvo has done with their wave piston, to reduce soot and increase combustion efficiency.

Cylinder head is a “dry deck” design. Meaning no coolant passes between the head and crankcase, zero potential for gasket failure.

Single camshaft, hollow, but larger diameter.

There is a stainless steel oil pan available for “highly corrosive” environments.

Main bear are now polymer coated to reduce wear.

In the notes my salesman took he has “greatly reduced EGR rate.” How much less, I don’t know, but if they’re able to get EGR down substantially and the decrease in soot generally, the A26 should have outstanding long term durability.

They had PIT, a research firm in Canada, test the A26 against the DD13, D13, and Paccar. D13 was at 7, Paccar at 7.66, DD13 at 7.69, and A26 at 7.71. The trucks were all spec’d the same and driven on a test route in Canada. PIT had tested other technologies as well and do a good job.

They recommend 1150-1250 downsped rpm and 1250-1325 in normal operation for maximum efficiency.

I’m getting the Valve adjustment done Monday, required at 120k and then every 300k after. I’m going to be there when they take the cover off so I can see inside.

I watched a YouTube video the other day with the Navistar and VW Truck and Bus CEO and they said Navistar will have a fully integrated power train in 2021 as well as more engine models based around the same design platform as the A26.

 

So they are slowly being integrated into the Scania-MAN family.