389 with X15 vs 579 with X15 vs 579 MX13

There's a girl on here selling her old mans 379 with a 12.7 you could get pretty reasonable if you have the cash.

 

I'm curious about the x15 to , they have an economy model and a power model
How much mpg difference between aero truck and classic with each x15
They should be on the road already

 

Our local Freightliner has an '18 Cascadia with 500HP twin stack X15 / 13 speed manual on the lot lol.

It's supposed to go some stupid miles between services if that's your twist, like 70K I think. Mine service is 20K per my warranty. 70K??? That's nuts.

 

I've heard that to , I change the oil on my 06 isx at 15 k , at 70 k I would be sleepless and cold sweat .
There must be some bypass filtration

 

Nothing special about the daycab im driving for the LTL fleet. 579 with x15 efficency 400 hp attached with a painful 10 ultrashit, 2.67 rear end, governed at 65 mph @1200 rpm. Driving in PA mountains, turnpike, 322, nearly empty, and gets about 7.2 mpg. When gross of 62-75k pounds, i get 6.1 mpg. Other than that, strong jakes compare to previous isx15.

 

Yeah that's not so great , would have thought it would do better. That's the Econ setup , even the axels are set for direct drive trans right? Maybe those crazy ratios kill mpg in the hills

 

Those ratios are purposed to have direct drive on em. Funny thing that they spec with an 10 speed overdrive automatic with those 2.67. 22.5 lo pro. Who knows. 13 speed and 3.42 with those tires could of been perfect if it had 500 hp. That 579 with x15 is truck im currently on cause my assigned volvo had been in the shop on a daily basis since they reprogammed some ####ty shifting parameters, increased torque (1750 when the tranny is capable of 1450). Broken ujoint, broken clutch ecu, PIECE OF ELECTRONIC CONTROL JUNK and I dont miss it!!