After checking all the easy stuff, filters, odometer accuracy, etc....see if you can find someone by you to swap wheels with for some stock size wheels. One tank of fuel, adjusting for your now smaller tires should give you a good idea how much yours are affecting your mileage.

 

the mods that will get you ALOT better miles is an air filter, a straight threw muffler (or cut it out, but leave the cat) and a programmer. I tow a 10k enclosed trailer and got 15mpg traveling at 65mph. I do get 23-25 mpg highway empty. I have stock wheels and tires tho. The wider tires you are running are hurting you, when mine wear out i am going for 285/70/17 instead of 265's for more distance travel per rotation with the same amount of rubber touching the ground. its also a combo of the restricted stock air filter and muffler. If your worried about warrenty, leave the programmer out. There are alot of little tricks you can do to improve fuel economy without a programer. the rokktek sensor is mainly for city driving, not too helpful over the highway. Switching to synthetic engine oil lowered my idle load 5% (as per what my edge says)

 

dude, as mentioned before its the width of your tires thats killing u. that much rubber on the road is alot more friction/resistance, couple that with the weight of the motor over those tires and your just plowing. height/taller gearing doesnt bother these motors as much. ditch the stock muffler and leave the cat,u will love the sound then swiss cheese the airbox and ad a good air filter, that will help tons.

 

Maybe so technically BUT who's going to stop me? We don't have emissions testing here in any shape or form.

Besides, my truck gets approx. 1 mpg more without that thing on there. I think it all balances out. I may emit more emissions, but I'm burning less fuel, saving money. Besides it takes energy to produce fuel which in turn produces more emissions and puts our country into futher turmoil. That's how I look at it anyway.

 

Man that mileage stinks... I get 18-20 hwy unloaded @ 65, and 12-14 hwy towing 13k... No programmer involved.

 

If you do the "cool tube", make your own, and the muffler delete there isn't really that much more noise. Mine drones a little between 75 and 80, below that I don't notice the difference in noise, but it does pull better!

 

Really no reason to remove you cat. After a years test, no diff. in MPG without a cat.

 

It's been said a million times but I would definitely try to get more air flow, maybe a rokktec sensor too (my buddy loves his 1 maybe 2 mpg increase). I really think your mileage will get better over time once your truck gets fully broken in, I would drive it like I stole it for a while to help assist break in, but of course while you're doing that you won't get good mileage, but I would give it some time.

 

When I took my cat and muffler off, I noticed my cat was pretty well plugged up (70k miles). With both of them off, I was getting about 2 mpg better than I had been. Plus I can smell the diesel much better, and there isn't a better smell in the morning.

 

You said it!

 

...I have always thought that I drove the truck easy. I try not to stomp the go pedal too often, however sometimes you just gotta do what you gotta do!!

Since Monday, I have been keeping the RPM's under 2000 every where I go, and right now my overhead is reading 18.2 MPG!!!! Now granted, my overhead is usually a minimum of 1 MPG on the high side, but this still would put me around 17 MPG which would be great and more in line with what I thought I would get.

I am thinking about some of the other items ya'll mentioned. I would remove the muffler, however this is my daily commuter and my tow vehicle for long trips and I don't want the family to have to scream at each other just to be heard. How noisy does it get with the muffler removed?

Swiss cheesing the air box worries me only from the standpoint of all the other stuff that can get in there along with the air. I have been using the NAPA Gold filters, would this filter be appropriate if I Swiss Cheesed the box? How many holes, where do I put the holes, etc? Would this damage my warranty?

Thanks for the info., keep sending it!!

Jason

 

I have a 2004.5 and pull a 33 ft. 10000 lb. travel trailer. You can see from my information below that I have 4:10 gears. When my truck was new I could not get over 16 mpg. Now with the mods the flash and 32000 miles I can get over 19 running 70 on the interstate. Pulling my trailer I have never got over 11 mpg.

Bill

 

1stTimeAround,

here is the info on the cool tube: dieselpowerproducts.com/PSM_Cool_Power_Intake.php

I've seen other people out sourcing the parts to do it alot cheaper. No problems with water intake (if that is what is your concerns). You'll have two areas to pull air in, so no vapor lock to create suction. Well that is unless you put the whole front end under water...

As for the muffler, I've hear that people that have gone with a donaldson muffler have had good results with lowering EGTs & retains the stock tone at cruz, but just a little louder a full throttle.

I have the Auroturbine where my cat used to be & a thru BMRP muffler in place of the stocker. It's nice at cruz, but at full throttle or lugging it, it lets you know. Not to loud, but the misses doesn't like it as much. I just wanted the big rig sound when I needed it. It does suit me needs, but it will be alot pricer than just putting in a donaldson.

I would check with the dealship on which filters they accept for replacement. I use fleetguard (cummins approvded) for the fuel & oil & have a Pro-guard 7 (also cummins approved) for my air filter.

 

My '06 Ram 2500 4x4 quad cab, all stock, with 13k miles on it is getting 9mpg towing a 8K lb fifth wheel camper. That is in FL, with the a/c on, running with cruise at about 70-72mph. I, too,, would love to know what I'm doing wrong so that I could get the 12-13 mpg that so many poster speak of!!!

 

My stock 2005 2WD QC gets 21 unloaded 80% highway, towing my 30 ft. enclosed Pace Shadow GT race trailer I get 13 to 14.5. Trailer is 6000 lbs empty. This is in Florida, AC on, running 65-70.

Ryan