Fuel Consumption

[Big Sky Bob]

I have a 2001 Dodge Ram 3/4 ton with fuel consumption problems. I have taken it to the dealer 4 times, 3 times re-programing ecm module, replaced transfer pump. Took it to Cummins - reprogramed engine, still only getting 8. 5 mpg towing approx. 6000 lbs and 14 mpg empty. I do have 265/75 tires. Any ideas?

 

[LSMITH]

Bob, there have been some guys that have cleaned the Intake Air Temperature sensor and have reported some substantial gains in economy. Use the search feature and you will find a lot of info on this, search under IAT also. The resistive values are available also to check and see if it is working properly. If you want to replace it rather than clean it and check it you should be able to get one for around $25. Hope this helps and if you have trouble coming up with info let us know and we can try to help.

 

[JR2]

Bob -

We need more info. How many miles on the truck?? Do you have any mods?? Auto or manual?? Do you have boost/egt gauges? Does this truck have any other problems or nosies you are not sure about?? Are you running winter fuel?? Does the truck lack power and get crappy mileage or is it gutless too??



You could put some of this info in your sig... that way everyone can see what you have.

 

[Vaughn MacKenzie]

Bob, if you have a 4x4 dually with Auto then you are not too far from normal. But like JR2 said, "details, details. . . "



I get 18-19 around town and 21-22 on the highway cruising 70-75.



Vaughn

 

[Big Sky Bob]

Ok, I will add info to sig. once I figure out how, but for now here is some of the info: approx. 15000 miles, 3/4 ton quad cab, long box,4 speed automatic,47RE, I have a pyro & boost guage, runs 18-20 lbs under full load, no other Mods. It does not lack power. I am currently using winter mix of #1/#2 fuel with no additives.

Hope this helps. Thanks to all of you.

 

[Okie-Go]

I can't help you much other than I remember reading they do a lot better after 20-25000 mile on them. Others may give you a list of things to check.

 

[Ramboy]

An EZ would probably help some, too.

 

[BigDaddy]

Big Sky Bob,



I always see a decrease of about 2 MPG with the winter #2 fuel verses the summer #2 fuel with my setup (see sig).



Since you are using a blend of #1 and #2 (AKA: Commerical Fuel), this may account for your lower fuel economy.



I would still check the other's (as outlined above) and perhaps the Air Intake System, boots, clamps, bolts, etc.

 

[JMichelson]

Fuel Mileage

If the tires are not the stock size, the first thing to check is odometer accuracy. The mileage on my 98 12-valve was off. After checking the accuracy of my speedometer I found it off 7% not a lot, but I was putting on an extra 7 miles for every 100 miles I drove. My tires are slightly larger than stock. Odometer accuracy is a easy and free place to start.

 

[TKilgore]

mileage

I have 17K on mine now and can't get over 16mpg empty no matter how I drive and get 12. 5 towing ~7500# no matter how I drive. Truck runs strong.

 

[JR2]

If this helps the best mileage I ever got was 20 and that way empty with a tail wind. The worst has been this winter at 11. 5. That was an entire tank in town in 4x4. I keep track of every fill up and at the end of the first year I owned the truck my average mileage was 15. 3. The most I ever tow is my snowmachine tralier at about 3K lbs.

 

[tcourse]

Sounds like it needs some big injectors



Seriously, check all your hose clamps. It gave me 2mpg back.

Complained to dealer for 10,000miles. MikeR showed me the problem in less than a minute.

.



TC

 

[smilliron]

That's not too bad of mileage...

Hey Bob, I've always heard of a lot of people getting pretty good mileage and thought I should be able to clear 15mpg also. Well, I can get 15, sometimes 16, pretty steady empty on the freeway at 82mph, but that's it. Have checked everything everyone mentions on here. One thing I've noticed is that the people with the great mileage seem to slow down just a bit and get a lot better mileage which fits with my best ever tank of 17mpg in which I drove 100 miles of that tank at 65 instead of my usual 82. I guess what I'm trying to say is that mileage does depend on a lot of variables, but it doesn't hurt to check everything such as boost leaks and IAT sensor.

Just my 2 cents...

 

[HTRDHLR]

My 01 has 1100 miles on it and I have not been real impressed but I figure its still real tight. Mine is a 4x4 dually and my last tank averaged 12. 6 mpg.