isx15 cm2250,enginee 2012, enginee lock up

[Hammerhead]

(10-21-2018 )Vanhvacr Wrote:  Thanks You Hammerhead.
Now i know why they burn too much fuel, 3200miles at $3.18per gallon burn $2500.

Can you give me some advise?

thanks you,

Yes, SLOW DOWN!
74mph cruising speed in a Class 8 vehicle is ridiculous.
Get your RPM up higher, 1500 is far more optimal. 13ish is ok if you're empty/bobtail while keeping your boost pressure at 10psi max. Any amount of torque load at that low of an RPM creates far too much piston skirts side load along the cylinder walls, increasing friction, which increases internal engine resistance which is inefficient. The extended "time" duration due to low operating RPM also allows the oil more opportunity to be displaced from the dragging components, thereby further increasing wear.

Read.
Read.
And then, read some more.
It's preached constantly on here, that excessive speed, low operating RPM (which combined increase engine torque loads), are next to shoot the largest contributing factor to premature engine failure.
Learning the correct way to operate the equipment you're operating is essential to increase your business margins.

The other suggestion is; if you're in Atlanta, then take your truck to Mr Haggs to ensure correct diagnostic procedures will be used to KNOW what is wrong, and why it went wrong so you don't repeat this mistake.

Good luck, and sorry to be the bearer of bad news...