C7 Fuel Mileage

[BBBEEBOP]

You say that your mileage is based on the MH computer. Have you checked on a long trip manually. I log all my fuel stops, mileage and gallons. At the end of the trip I'm sure what my average fuel mileage is.

[Vegasdan]

Originally Posted by Kirstcc

My Journey with a 350 Cat pullin a Jeep only averages 5.9 per the dash computer.
How can I improve this?
I also don't think it has the power it should.
Where do I start?

How fast do you drive? My 3126 gives me 10 at 60 to 63MPH. How clean is your air filter?

[Pusherman]

Originally Posted by Kirstcc

My Journey with a 350 Cat pullin a Jeep only averages 5.9 per the dash computer.
How can I improve this?
I also don't think it has the power it should.
Where do I start?

My understanding is that the mpg computer on the prior dash gagues manufactured before 2006 are not resettable. Therefore you get the (dis)advantage of all the early poor mileage on the coach still in your mpg calculations today. I'm sure you are getting better mileage today. Call 1-800-FTL-HELP and give them the last 6 digits of your VIN. They can verify the computer reset capability.

You might want to stop by a CAT shop to see if you have the latest engine firmware. I think there is a reflash made available since your coach was manufactured, which may affect your engine performance, acceleration, etc. Freightliner can tell you if/when the flash update was made available based on when your engine was manufactured.

I have the latest mpg computer from FL and it is resettable. I am now averaging about 8 mpg with 16K miles. I'll do the valve adjustment after 30K miles. They do get better mileage with age.

[Kirstcc]

Originally Posted by KennethM

Kirstcc, do you know the maintenance history since new and has the the engine had the valve adjustment maintenance done? "Run the Top" maintenance does a number of things to the CAT and one indicator of needing it is lower milage but if it has been done many things can cause that low milage.

Ken- No I don't know the maintenance record.
It has 27K miles on it now. I will research that Thank you. I am due for an oil change and the air filter is getting close. about 80%. But I think it should still get better than 5.9.

[Kirstcc]

Originally Posted by Vegasdan

How fast do you drive? My 3126 gives me 10 at 60 to 63MPH. How clean is your air filter?

Dan- I do drive a little faster than most but I try and leave my foot out of it on the climbs and coast on the down hills. Filter is getting close.

Pusherman- you are correct, I cannot reset my computer however it has a instant mileage mode and I catch myself staring at it. 2 mpg up large grades and 200 mpg down hills. but on a flat run and a constant speed I'm never near 10 mpg. I will check on a reflash. That would be great. Thanks for the info.

BBop- I will check it manually and find out forsure. Thanks everyone.

[ninos]

I just drove my 06 discovery with a c7 330hp from new jersey to florida cruised @ 65 on cruise control and I got 7.6mpg and that is a real number because I made the calculations my self with paper and pen, and all the water tanks empty, the drive was all pretty flat no mager hills.

[JayLodge]

7.5 That's pretty much what I get with a 2006 C7 having only 14,000 miles on it.

[ninos]

just drove 1100 miles from florida to new jersey and i got 8.2mpg cruising betwen 63 65mph on cruise control and i got 26000 miles on my c7.

[deltastar459]

You folks are making me feel better, C-9 Cat 400 HP consistant at 6.8 to 7.3 Has anyone had any experence with the Pittsburgh Power Box Computer application for Cat engines.......

[ninos]

I dont know if you are talking about the same thing I got from brazels rv performance but you are talking about that It Is great the power diference is unbellivable and the fuel miles Is a bit better, I love It Joe.