I own a late '03 ram 2500, extended cab, long bed, cummins HO (turbo). From day-one, my highway mileage has been around 18+ (no head wind!!!). Towing my 5,500# RV I'm at around 11-12 average. This is my first diesel truck (I'll never go back!!!) and I was told by a few friends that own various diesels that around 25-30K miles I should see my mileage start to increase somewhat.

I can't say I've noticed any improvement @ 33K miles.

Is this just a tale, or has anyone noticed any kind of improvement as the engine begins to break in???

Also, I'm sure this comes up a lot, but I'm considering a chip and intake modification and I'd sure like some input. I've read that some chips will increase mileage 3-4 mpg (unloaded). At today's fuel prices I'd think it would pay for itself quite nicely. Any help here would certainly be appreciated.

Thanks...

 

I started off at 13 when I rolled off the lot, 20K later if I'm easy I can hit 18. fuel mileage tanks quick with PSD's and d'maxes around

anyway, if ou want a little better mileage try 8-16oz of Power Service with each tank. you can get the stuff at wally world for abour $5 for a 32oz bottle and the stuff will pay for itself in the first tank. Ive averaged about 1mpg better with 8oz and almost 2mpg better with 16oz. Ive done some research and testing with different mixes and additives like Marvels mystery oil and two stroke engine oil. MMO did give a little better mileage, and knocked down some injector noise and engine rattle. The two stroke oil silenced alot of ratteling better, but gave no increase in mileage.

the best mix I came up with so far has been 8oz of MMO and 16oz of PS. this netted me an average of 2.5mpg better than no addatives. plus the engine ran smoother and quieter (like the cumins could get any more quiet[8D])

Now, about boxes. what you have hear IS true. any box on the lowest setting will give you better mileage. 3-4 does seem to be the average like you said. some boxes will add as much as 140hp, I have no clue what that feels like, but many have reported as saying they see asphalt flying in the air behind them. I'm unsure how true that statement is, but it sounds cool none-the-less.

the two boxes I hear that have the best sucess rate have been the Quadzilla box and the Van Aaken C3.2. the Van Aaken box is a timeing/duration box only and has been reported as beeing the hardest box for the dealerships to find it's mark after removal.

hope this helps some

 

If you can still find one somewhere, issue 31 (on newsstands earlier this summer) of "Trucks off rod accessory guide" had a comparison of 11 diesel boxes.

All the best.

 

I have had the quadzilla race box on my 05 for a few months now. My truck has the 4.10 gears and i dont usually baby it. normally i leave it in the 100 hp setting. 130 is crazy and good fun but i feel like it isnt as smooth as the lower levels and i believe this is because i still have stock intake and exhaust. also i believe it needs more fuel for a good run on that setting. dont know for sure bout that till i get a fuel pressure guage. best so far is 18.3 mpg hiway on the 100 horse setting. no additives either. id say driving the truck new and stock to getting the truck broiken in with 12000+miles and driving on the 100 horsepower setting, i picked up on average, 1-1.5 mpg increase. not that great but then again its hard to keep the foot out of it! In a few weeks ill have more things to test. gonna be going to bigger tires which will reduce my overall gearing and that will be good. Also looking at the van aiken box for down low, intake and exhaust help as well. further down the line ill be going for a cam and injectors. Then maybe a turbo. hopefully that will be the end. LOL

 

hey Tom. . .Ive been hearing the same thing about the high HP settings on all the boxes. You can feel the power is there, but in the high RPM's it kinda starts to drag due to de-fueling.

one of the best setups would be the 150gph FASS system. For those with the lifter pump this system replaces it with a more powerful and MUCH higher flowing unit. for the 05's it can be used inline with the stock in-tank pump.

if your planning on increasing the power much past what you have right now your next investment should be one of these systems. OH, it also replaces the stock fuel filter.