i have two questions
 

the first is my mpg is 13-14(according to overhead display), my truck is sittin on 315/70r17 goodyear wrangler duratracs, it straight piped an has a wet filter cai, and a 2.5in leveling kit.is that correct mpg? next question, about 5ksince my last oil change i checked my oil and there was very little. the bottom part of my truck has noticable amounts of oil on the axel an traction bar. it looks like the crankcase vent tube is pissin it out is that possible that it could piss that much out?

ok first the overhead LIES!!!! If I remember right the stock tire on a dodge 2500 ends up being a 30 or 31" tire. your 315/70/17 is a 35 correct. So you divide 30 into 35 and you end up with .85 and change the difference is 15% so when you hand calculate, total miles driven(odometer) plus 15% then divide by total gallons you pump into tank and walla! true MPG. overheads are usually high but since you have taller tires it is way off. then again if you drive it like you stole it then it might be spot on:s:

Some oil is okay, but it sounds like you have alot. i would get that checked

i had the same size tires on my 2004.5, your speedo is also reading 4 or 5 mph slower than you actually driving. most programmers have a feature to adjust for the taller tires. this will aslo correct your overhead reading.

how many miles are on your truck? i had the same problem with my truck forcing oil out the crank case vent (mine went around 180,000). at its worst i was pushing out half a gallon every 500 miles. the rings in #1 and #6 went and took the bores with them. while the engine is running take off the oil filler cap on the valve cover and see if the crank case is pressurized(it will look like a train puffing out smoke). if so have a compression test done. if the bores are gone a new engine or sleeving are a few options. this is getting to be a common problem. best of luck, hope you don't have the same problem as me.

you may have a cracked injector. but if it is cracked your dipstick should be way over full of oil and diesel mix. i cracked a Injector on my cr and i used a 1/2 tank of fuel in 1 hour. depending on what programmers your running it will through your mileage off on your overhead. hope this helps