Ok folks here is our problem.We are driving a 2009 Columbia with a MBE 4000 and 358 rear ends.Our fuel milage is in the gutter.Something like 7.8 to 8.1.At 65 the rpm's are 1481 or 1482. So if anyone has any suggestions it will be appreciated.Thanks Bobby and Paulette thorn.
Need some help
- Thread starter ONESTACK
- Start date
I'd start with the charge air cooler. First, start with the boots that attach the cooler to the tubes that lead up to them. That will also cause a fairly noticeable loss of power. Then, I would get the vehicle into a Detroit shop, or your trusted mechanic to do a test for leaks. Make sure you find out if there are any leaks, not just what is "within specs".
You didn't mention whether or not it was a straight truck or a tractor. I'm assuming straight truck.
I would also ask for a cylinder balance test, which, I believe, shows injector function.
Is the crappy mileage a recent thing? All filters recently changed? How about alignment? How long ago? Wheels balanced properly? What brand and model of tires? The rolling resistance on different brands matters greatly.
There's a start. I, along with several others here, listen to Kevin Rutherford's radio show on satellite radio, Trucking Business and Beyond. Midnight on Siruis 147/XM....not sure. Also on weekends from 1600-1900. Kevin is a fanatic about improving fuel economy, and the direct dollars it keeps in your pocket.
Hope I've helped.
You didn't mention whether or not it was a straight truck or a tractor. I'm assuming straight truck.
I would also ask for a cylinder balance test, which, I believe, shows injector function.
Is the crappy mileage a recent thing? All filters recently changed? How about alignment? How long ago? Wheels balanced properly? What brand and model of tires? The rolling resistance on different brands matters greatly.
There's a start. I, along with several others here, listen to Kevin Rutherford's radio show on satellite radio, Trucking Business and Beyond. Midnight on Siruis 147/XM....not sure. Also on weekends from 1600-1900. Kevin is a fanatic about improving fuel economy, and the direct dollars it keeps in your pocket.
Hope I've helped.
What is your fuel mileage and speed if you get the RPM's down to 1250. Going to have to slow down some and see what happens at that speed. That truck appears to be spec'd to run 55 mph
We have a CAT 300 6 speed auto 488 rears if we get to 60 mph we get b below 9 mpg
We have a CAT 300 6 speed auto 488 rears if we get to 60 mph we get b below 9 mpg
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We have a MBE4000 with a 3.58 rear end. At 1400 RPM we are doing 63 MPH and get about 10 MPG. At 60-62 we get between 10.5 and 11.5 MPG. That of course depends on wind, load weight, reefer use etc. Our truck weighs in at 30,000lbs empty.
