2026 International LT: Should be bringing it home tomorrow.

[Mike]

Putting the decals on at the dealership today, and unless they run into problems they are also moving my starlink antenna from the old truck to this truck. Title is being overnighted, and as soon as it arrives tomorrow morning I will be taking off to Little Rock to get the IRP done on it and grab some IFTA stickers.

Will be moving into it tomorrow evening and Saturday.

S13 engine (400hp, 1850 torque), T14 transmission, 2.15 gears.

 

[Duck]

S13 engine (400hp, 1850 torque)

Is that all that was available?

 

[Mike]

So much for bringing it home quickly. Ended up bringing it home Saturday. There was a shake in it that was indicating a steer tire issue to me. That was supposed to be taken care of. I drove it home, and it wasn't.

I was going to go ahead and get my gear put inside, then take it back to them on Monday (yesterday), but when I was walking around the truck where I park it, I heard air. The air was coming from the leveling valve. Spoke to the salesman, he let the guys in the shop know about it, and I took it right back that day. However, they wasn't comfortable with diagnosing it, so it ended up setting until Monday anyway.

Monday seems to have been an absolute waste of a day for them. Supposedly, they were working with it, and was going to adjust the leveling valve, and the air leak had stopped. Today, it reappeared, but they weren't able to adjust it because it takes some new special tool. Now, the tool won't be here until in the morning. I feel like it is going to need a leveling valve, but I'm not allowed to diagnose it for them.

As for the tire issue, they are now taking tires off of another truck to put on this one to test drive it and confirm which one is bad. Because it is a warranty issue, they can't simply replace both tires.

This has been the longest truck purchase saga I have ever experienced. I'm hopeful that I can get the truck by tomorrow afternoon, but not optimistic. Everything about this is just taking too long, LOL.

 

[Mike]

Is that all that was available?

I could take it home at 515hp, but I am going to run it at 400hp. I am looking for maximum fuel economy out of this truck.

As mentioned, it has 2.15 gears, and it is an overdrive transmission. Deep gear reduction for startup 20.81:1 (first gear and reverse). Will run in direct drive under heavy load, typically until you get over 70mph, but will go into overdrive sooner when empty or under light loads, depending on terrain. It's designed to run most of the time in direct (13th) though.

 

[Duck]

I could take it home at 515hp, but I am going to run it at 400hp. I am looking for maximum fuel economy out of this truck.

If you want fuel economy, just drive it for fuel economy. Does it have a boost gauge?

 

[Mike]

If you want fuel economy, just drive it for fuel economy. Does it have a boost gauge?

It does, but my only use for it at this point is to check it for changes from the normal to indicate problems.

It also has cruise control, which is what I choose to let control things most of the time these days. You may be able to do a little better if you are hyper focused on using your foot, but it's not worth it to me these days.

Nor is the horsepower, not with today's engines. Today's engines perform most efficiently at low RPM's. So, even with higher horsepower, the engines produce virtually the same horsepower at the lower rpm's so you aren't gaining much by going with more power. Can you climb the hill a tiny bit faster? Yes, but it's going to cost you, and your are most likely just going to run up to a slower moving truck anyway.

I'm not looking to be in the 8-9mpg range, I'm looking to be pushing more towards 10 and possibly better on some runs.

 

[Duck]

It does, but my only use for it at this point is to check it for changes from the normal to indicate problems.

It also has cruise control, which is what I choose to let control things most of the time these days. You may be able to do a little better if you are hyper focused on using your foot, but it's not worth it to me these days.

Nor is the horsepower, not with today's engines. Today's engines perform most efficiently at low RPM's. So, even with higher horsepower, the engines produce virtually the same horsepower at the lower rpm's so you aren't gaining much by going with more power. Can you climb the hill a tiny bit faster? Yes, but it's going to cost you, and your are most likely just going to run up to a slower moving truck anyway.

I'm not looking to be in the 8-9mpg range, I'm looking to be pushing more towards 10 and possibly better on some runs.

Just to put things into perspective, my diesel pickup gets 14.5 mpg bobtail.
My neighbor's old work van got 10 mpg with a gas engine.

 

[Mike]

Just to put things into perspective, my diesel pickup gets 14.5 mpg bobtail.
My neighbor's old work van got 10 mpg with a gas engine.

Yep, that is how far we have potentially come now with these engines when spec'd and operated for maximum efficiency.

Honestly, focusing on fuel economy is probably the main thing that kept me in business over the past couple of years.

 

[Rigjockey]

Yep, that is how far we have potentially come now with these engines when spec'd and operated for maximum efficiency.

Honestly, focusing on fuel economy is probably the main thing that kept me in business over the past couple of years.

Especially important now with the high price of diesel fuel even if you get a fuel surcharge.

 

[Mike]

Fueled up on the road today for the first time since filling it up at home. Can’t accurately gauge what to expect from this, but it was a couple short trips bobtail to the shop and back before hooking it to the trailer to get the first load. 60 mile deadhead to pick up dog food in Joplin and head toward Phoenix.

Gross weight is 79,400.

Stopped at the TA in New Mexico west of Amarillo this morning for fuel. 91 gallons, 8.89mpg on that first fill up. That’s climbing in elevation and dealing with stout cross winds.

Today, from there to the Continental Divide, computer showed an average of 7.4mpg. That is another big climb, and headwinds gusting over 40mph all day long.

Will cross Arizona on 40 tomorrow to Flagstaff, then south to Phoenix. Will be interesting to see how it performs in the wind again. With the addition of rain and the climbs on this route.

So far, I’m impressed.

 

[Mike]

Don't have exact numbers yet, because I don't update this for a running average on a regular basis. That said, the truck has averaged over 10mpg overall up to this point, that includes another heavy load out to Arizona, and a heavy load of chemical totes from Yuma back to the Kansas City area.

The last fill up was yesterday, looks to have fallen just short of 10mpg on that specific fillup. 9.68 to be exact, but with the load hauled and the route, I will gladly take it.

This is all with setting the cruise at 62 on the interstate and just letting it do it's thing. No extra efforts beyond just slowing down.

I would like to get it on flat land and lower elevation for a while to see what it is capable of in that environment, but the loads are just paying too good going out west right now to keep me away from there.

This is roughly 8000 miles tracked.

Got the truck aligned while out in Arizona. Would have gotten a lighter load out of there going back to Memphis, but blew an air bag on the trailer 15 miles from the shipper and lost that load. I hated losing that load because it was just dunnage weighing about 30k and paying $4.35/mile back to Memphis, plus an additional $400/day for three days of storage that I was going to spend at home. Warehouse out in Arizona needed it gone immediately, warehouse it was going to in Memphis wasn't going to have room to take it until Tuesday.

 

[Electric Chicken]

I dont know how I missed this thread. Congratulations on the new truck. Your mpg sounds impressive.

 

[Electric Chicken]

What RPM are you turning at 62mph?

 

[Liam Riley]

Hey bro, little late to the topic. Wishing you all the best with it. Stay safe!

 

[Duck]

Don't have exact numbers yet, because I don't update this for a running average on a regular basis. That said, the truck has averaged over 10mpg overall up to this point, that includes another heavy load out to Arizona, and a heavy load of chemical totes from Yuma back to the Kansas City area.

The last fill up was yesterday, looks to have fallen just short of 10mpg on that specific fillup. 9.68 to be exact, but with the load hauled and the route, I will gladly take it.

This is all with setting the cruise at 62 on the interstate and just letting it do it's thing. No extra efforts beyond just slowing down.

I would like to get it on flat land and lower elevation for a while to see what it is capable of in that environment, but the loads are just paying too good going out west right now to keep me away from there.

This is roughly 8000 miles tracked.

Got the truck aligned while out in Arizona. Would have gotten a lighter load out of there going back to Memphis, but blew an air bag on the trailer 15 miles from the shipper and lost that load. I hated losing that load because it was just dunnage weighing about 30k and paying $4.35/mile back to Memphis, plus an additional $400/day for three days of storage that I was going to spend at home. Warehouse out in Arizona needed it gone immediately, warehouse it was going to in Memphis wasn't going to have room to take it until Tuesday.

Have you made any empty runs long enough to be math-worthy for fuel economy?

It's interesting how a truck can more than double it's empty weight without doubling it's fuel consumption.

Lots of cool newtonian physics and thermodynamics stuff to consider.
And you can completely ignore wind resistance because it's the same loaded or empty, given the same weather conditions.




Any idea what the efficiency of the engine is? Specifically what percent of the fuel gets converted to mechanical energy as opposed to the amount wasted in the form of heat?