Waiting on New Trucks thread.

Oh yeah I'm sure that's just a side gig for every single one of them.

 

I loaded a 40’ container once a few years back. That’s like the same thing right?

 

This engine is designed to run <900rpm. You should read up on it. It’s not the D13 of before. Likewise, the DD15 Gen 5 is capable of doing the same. Both engines pull <2.20 rearends.

 

I’ll observe from afar on those.

 

Now here’s something. Let’s see what you fellas think. Only one of these can actually be built, the other is an exercise of the imagination.

A new 579 with my specs: 565/2050 X15, 20918B Eaton, 3.25 rears, LP24.5, 80” midroof bunk, 280” WB, exposed boxes/tanks. Doing the work I do now that my 389 does 5.92 mpg lifetime on.

vs

A new 389 with the fuel sipper spec of the week. One of these downsped Detroits or Volvos, say 475/1750 to 505/1850 range, matched 12 speed automated box, 2.26 rears, LP22.5, 78” midroof no cap/dome, 245” WB, exposed boxes/tanks. Pulling a dry van with all the aero goodies (skirts, tail, etc)

Which would get better fuel mileage?

 

Sad he could not make it even making that MPGs

 

The D13TC is designed to like those low rpms. Hint the reason they are downspeed engines.

 

Well for starters your lower one can not be spec'd so it is not gonna do anything. You need to have at least a 13 speed to get into the 2.26 gears at least on the Volvo. So your first one is gonna be the only one that can be built so it would be that one.

 

For the first truck to be a true comparison the sleeper gap would have to be the same, not the wheelbase. My last 579 was 265” and had the sleeper gap of a 389 with 290” or so wheelbase.

You could get close on the second truck with either the Efficiency X15 at 450 or the Paccar at 455 with the 12 speed and 2.64 rears. You’d have to go with 2.79’s if you wanted the regular X15 or the 510 Paccar. Not a downsped drivetrain, but would be interesting to see what it would do.

 

550-600/2050 /18/11R24.5/3.70

thank you very much