Do you have larger tires than stock and if so have you taken this variable into consideration?
GPS is the most accurate means of calculating mileage. My speedo is off 10% on GPS. I get 18 to 21 mpg depending on the amount of highway miles I drive. Stock motor presently, BHAF, 285/75/16 tires, 5 speed. An automatic will cost some mileage, i would say a couple mpg.
How much do regard as a Ton of money? First and formost you should free up the exhaust. At the very least, remove the cat ( if your truck is equipped with one) replace it with a straight pipe of same diameter, then move on to the muffler. Replace with a straight through design (whatever manufacturer is up to you) or go straight piped. Going straight piped will be crazy loud tho. MBRP or Magnaflow are good diesel mufflers, THere are others of similar design, but that may take some research. Ebay is a good resource. I got a brand new MBRP stainless muffler on Ebay auction for $37 bucks, shipped. Very lucky on that one. Anyway, you can move up to the intake and free it up. One option is to replace your air filter with a high flow aftermarket drop-in dry element (washable) or oiled design, BUT stay away from K&N (not very efficient and lets too much fine dirt through). You can also "Swiss-cheese" the stock air box, by drilling holes at the bottom of the airbox to let more air flow through. Another mod would be to remove that big *** air diffuser thing ( big black cylindrical doo hickey in your intake tract, if equipped. Looks like about the size of a coffee can). Replace with similar size of pvc pipe. If you later decide to get a programmer, get gauges first. You will need Pyrometer to monitor EGT's, Trans temp gauge, Boost gauge and fuel pressure gauge. This is pretty much mandatory before getting any programmer, or going on with other more serious mods.
Word of warning: THis is addicting!! Once you start modding your truck, youre gonna want more and more. The mods Ive covered can be done "on the cheap" and they do work. Good luck and have fun!
Whoops! I based the intake mods described above on the factory air filtration system that was equipped on my 2006 CTD, before I changed it. My bad. I dont actually know what your factory intake filtration looks like. But, the swiss-cheesed stock filter box will work none-the-less.
Last edited by Bigg Redd; 01-12-2014 at 12:46 AM..
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