Better fuel/power Acert C-15

Thread starter #1
Hey guys I'm running and 05 Freightliner Classic XL with a 435 twin turbo Acert C-15, 13 speed, and 3.55 rears. I've been trying to get better MPG and power out of it but I just can't seem to do it. I've tried a few different things from add ons like Air Cells, Turbo 3000 D, to changing driving keeping it under 14-1500 RPM while cruising. I'm debating on converting to single turbo but not really excited about spending upwards of $9k. Anyone got any suggestions?
 

mndriver

curmudgeon extraordinare
Supporter
#4
Get a Detroit or Cummins motor.

Cats aren't known for fuel mileage.

Having said that, if you are in the 5.5-6 5 range, you're getting typical truck mileage.

Slowing down to 64-68 is about the most beneficial. Probably adding an aero package to the trailer.

Test your charge air and make sure it's not leaking.

I had asked a buddy explain the difference of a tune of cat vs a Detroit. It's two totally different processes because I was looking at buying a 6NZ truck and an acert.. he explained how the twin turbos was actually a better setup. No I can't pass what he said on. I understand it. Just not well enough to explain it how he did from a month old conversation.

A well maintained engine without all those gimmicks, manage your tires, close your air gap to the trailer and light loads are the secret to fuel mileage.

And don't idle.
 
Thread starter #5
About 1.2 Mil gettimg between 4.8 to 5.1 running 65. This is the first cat I've had I have 6 other trucks with Detroits or Cummins that i can get 6+ out of them, so this is a whole new beast to me lol.
 

ironpony

Professional Pot-Stirrer
Supporter
#8
Low rolling resistance tires will have a positive effect - you don't need wide singles to get it.

What are your drives and steers? Do you own your trailer?

You might get as much as a 0.5 mpg boost.
 

Injun

Rabid Squaw
Staff member
Supporter
#10
About 1.2 Mil gettimg between 4.8 to 5.1 running 65. This is the first cat I've had I have 6 other trucks with Detroits or Cummins that i can get 6+ out of them, so this is a whole new beast to me lol.
That's about what you're going to get out of a CAT, especially in that brick. It's a workhorse, not an economotor. Nobody has ever bought a CAT for fuel mileage.

Slow down to 62 and skirt your truck. All of the gizmos and gadgets you attach to the engine or fuel line are nothing more than snake oil designed for no purpose other than to line their marketers' pockets.
 
Thread starter #11
Well would be nice if i could pull a damn hill. I have problems even with light loads 15 - 20k if it had no problems with that then i would see the lower MPG as acceptable.
 

mndriver

curmudgeon extraordinare
Supporter
#13
Well would be nice if i could pull a damn hill. I have problems even with light loads 15 - 20k if it had no problems with that then i would see the lower MPG as acceptable.
I run a Detroit and most cats and Cummins and Detroit's **** me off.

Ok, stock fleet tunes.

Any truck on the road that's an O/O can stand to be retuned. Most shops will set them up on the conservative side of power for fleets and tell you, " that's just how it is.". Bullshit if you ask me.

The potential is there for your truck to get both power and mpg. Just how much do you want to spend on it.

Start here. Call them on Monday. Buddy of mine has his 5EK 3406E tuned by them. He's happy.

Diesel Freak, Performance Harnesses
 
#14
I just saw an advertisement for a BullyDog big rig tuner. I've used both the gas and pick up diesel versions and they made a massive difference in power and economy. It might be an option.