Great Fuel Mileage - Newbies Look

[HeavyHauler]

Soon after I joined this forum, I posted a thread regarding the poor fuel mileage that I was getting with my new 1-ton. I was getting 16 MPG on average and sometimes it even dropped into the high 15s. I was very concerned and began researching some reasons as to why my mileage was so low. One of the reasons I bought my truck was the great fuel mileage that all the other Cummins owners bragged about.



I cleaned the IAT and switched fuels, but still no improvement. I finally decided that I had a failing lift pump. Before I had it checked, I decided to drive around 60 MPH solid one night coming back from a race in Georgia. When I checked the mileage when I got home, I had averaged 19. 3 MPG. What a relief!



Anyway, I average around 19. 5 MPG now with a truck that weighs almost 5 tons. I learned that the CTDs are more sensitive than gas motors and if they're drove at 65 or more, the mileage drops fast.



I think if I ran solid on the highway with little idling and no A/C, I could easily hit 20 MPG.



So I just wanted to share that with any new members that were concerned about low mileage with their new truck. I've learned to take my time when I travel now and it's pretty satisfying when I see that I've averaged over 19 MPG with my truck.

 

[dpuckett]

Also, keeping your foot out of it in town will help, too. I have too much fun in mine (I average 18, but have seen 20 with a light foot). How a 13 year old, 5000# pickup with 10x the miles can outrun little ricers that are 2000s and up, is still beyond me, but still nonetheless. I have the 4. 10s, and have gotten 23mpg with mine at 62 mph on a hwy trip from Colo Springs to Greeley and back.



So, get a pyrometer, boost gauge, and read up on driving with gauges here- www.dieselinjection.net and click on their B & C series booklet. I see no reason for you to be unable to achieve 20 mpg or better on a regular basis.

Daniel

 

[thames1948]

I go between 12 and 13 mpg's and I don't do over 65 and I am a newbie so what am I looking at? 2400 miles and nothings changing. Its a 600 thing with the bad mpg's.

 

[SRadke]

If the 600's are anything like the 03's all they need is a little break in time and a timing box. My TST box on setting 1 (timeing advance only, no additional fuel) will gain me an instant 1 mpg.



-Scott

 

[thames1948]

I think if the 600 were like the 03's ,I wouldn't be in the 12 mpg's. and dissapointed at the lousy milage. I don't see the 5 to 7 mpg's that are missing will arrive at break in.

 

[Cummins Pilot]

I have no idea what my mpg is. I can't keep my foot out of it. Plus I love making every other diesel out there look slow when I'm hauling a 26' trailer up hills. Even 454, 460, & V10 gassers.



I know it really makes my economy go down. But I can carry up to 125 gallons of fuel.



Around town I ussually get about 300 miles to a tank and pick up about 25 gallons. But this is also #1.

 

[dpuckett]

thames1948- are you getting your MPGs from the overhead console, or doing the math at fill up? The computers arent always accurate. I get irritated when I drop below 18. New technology for ya.



ALso, get into it now and then; help the new parts seat well. You SHOULD see slight improvement over the course of the next 10-15K. THese engines dont get broke in till around 10-15K, more time and miles till break in, the easier you are on it.

 

[JKurley]

I've got a 93 5speed -very consistent 20 mpg @ 75 mph throughout the western states-when I go from Denver to Farmington NM over Wolf creek Pass, I average 24 mpg. Mine is 2x4 with 800lbs salesmans samples in bed under an aluminum shell.

 

[n5ifi]

I've got a 2002 that barely gets 15 at 70 mph. It has 55,000 mile. I cant figure it out.

 

[klockk]

I have a '03 4x4 LWB AT. .

I am now at 8K Miles...

When I was driving to the ski resort (30 Miles up, one way) 3 days a week over the winter, it crept up to 16mpg...



Over the last month, I have been driving around town only and it has dropped down to 15. 1mpg.....



I usually get at LEAST 450mi/tank



I am making a trip to the Portland, OR and then to Newport area next month... I'll have to see how a nice long haul (mostly empty) on the freeway for 6+hrs straight will do for my mileage. .

 

[SRadke]

Sounds like good trip klockk. I'm not fond of that big city by the river though.



I made a 500 mile round trip to Klamath Falls this past weekend for the truck pull I averaged 65-70 running in the low 8k weight range with my TST on 4:4. Simply driving, I didn't get passed but I wasn't pushing things either. I penciled out 19. 7 mpg when I filled up on monday. Can't complain about that.



-Scott

 

[klockk]

You Auto or Manual Trans?

I would like to see 22 to be quite honest. .



A co-worker seems to have managed to pull 24-25 a couple times in his '03 SWB Manual 6-speed. .



I figure a 6-speed manual will always get better mpg than my AT...



We'll see how things average out... .

 

[SRadke]

I've got a 5-speed and 3. 73's. I intend to put some taller tires on and I believe they will help my mileage a little but I don't expect much better than 20, this truck is just too heavy. The added timing of the TST box brought me up from 18 mpg.



-Scott

 

[klockk]

Oh. . It's you!



I recognize you (if memory serves me correctly. . )

Don't (didn't) you work at HP out there in CornValley?

I spent 13 years there. . then transfered to Boise in Summer of '00...



Small world!

 

[FDrake]

My 02 Ram2500 6 stick got 12MPG towing. My new 04 Ram3500 gets abut 10. I got 17 around town in the 02 and lucky now to get 15 with the 04. Is this what I can expect from now on? That sucks. The dealer told me I have the latest flash too.

Frank

 

[SRadke]

Don't think so Klockk. I've been here all my life but never worked at HP. Actually I'm a little outside of town and avoid it as much as possible.



-Scott

 

[rblomquist]

Stock ATs are pigs on gas. I instantly picked up 1. 5mpg when I got my aftermarket trans.

 

[Guest]

Mine keeps getting better and better with a few more miles tached on it... I get an average of 20 on the highway to work. .

 

[ndurbin]

Mine varies alot because I do alot of different types of driving. I got 10 mpg w/ a slipping trans. when towing (which isn't bad for a slipping trans. ). Around town I get about 15 if I keep my foot out of it, which is hard to down now with the #10 plate in. Out on the highway I get about 20-21 cruising @ 75 mph.



Nathan



Oh... ... ..... mine is well broke in now with about 10,000 miles on the new transmission.

 

[CMaster]

I hate being called a lier, but here it goes anyways. I had a hard time getting 17 mpg untill about 20,000 miles. Out of desperation I drilled several hloes in the bottom of my air filter box and replaced the filter with a stock, NAPA filter. I now have 29,000 miles and got 21. 5 mpg on my last tank. 65- 70 mph on the highway, and since i,m stock, i keep my foot out of it in town.