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High performance products for the newer electronic controlled diesel engines.

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Fuel MPG improvements 2012 ISX

We have a 2012 KW with a 525 HP ISX and fuel mileage is a disappointing 5.5 MPH. Since half of our mile are in CA we need to take that into consideration.

What can Pittsburg Power do to help and approximate cost?


Mike Broaddus

707 639 7600


'''We pretty much run this T660 @ 60 MPH 90% of the time and 65 MPH 10% of the time (we try to get a run at hills).

It only has 12K miles on it so perhaps my concern is premature. I guess I need to sit down and make a checklist on everything that can be done and prioritize.

Thanks for all the good info, guys!'''

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Most Helpful Answer

Since you run CA may have to leave the engine alone. Start with the basics slow down invest in some no idle products low RR tires don't forget about that trailer back there tires bearings etc. also the engine really needs a solid 100,000 miles to break in and loosen up.

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I have a cummins isx 500 hp Been a few problems with it Cummins can change the parameters in the computer I have some changed and there is a great improvement in fuel mileage engine response and overall

performance We are presently still working on the parameters on enabling and disabling them Its a slow process but we are on the rite track thanks best of luck

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Mike, there's lots of things you can do to improve fuel mileage.

First, Have Cummins adjust settings in the engine.

Run slower.

Invest in devices to make you idle less and devices to make your truck more aerodynamic.

AirTabs, an APU (such as Hodyon's Dynasys or Thermo King's TriPac E), and Michelin XDA Energy or X One XDA Energy Tires would be a great help. So does the FASS system, which removes air from fuel, further increasing mileage.

Don't forget about the trailer- skirts, fairings and low RR tires. Bearing adjustment and alignment are also important.

BTW, which model of KW do you have? W900s are terrible for fuel mileage when equipped with EGR engines. T660s and T700s should be better than 5.5 regardless of engine or tires, simply because of their aerodynamics.

Make sure when you calculate your fuel economy, you're doing so on paper- not relying on the truck's ECM or on-board computers.

These are just a few things you can do. There are over 40 factors that can affect fuel economy. Most are driver habits, though some also have to do with the truck body and the engine. Check this out:

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Mike will be eternally grateful.
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