14.4mpg (me too) - my complete maintenance "kit"
I have also been in a determined search on how to get my 2007 Nitro SLT completely loaded (with 20" R/T wheels/tires too) from 14mpg - that's right, a SHOTTY 14.4mpg, to 20mpg in the city. I knew it could be done! Just 6mpg to go. While I haven't reached that yet. I have hit 18.3. Still good to me but I will continue my quest. I have a limit I want to invest on this research (~$500) to get that elusive 20mpg in city. Well, funds are limitless but I am setting my cap (hehehe, till I hit it, then it may expand a little

).
So far I have installed the following items, although not always the "BEST" brand available, very good. I have listed the items, what I have found to be the "best," and what I installed.
Spark Plugs = E3s are best (only available by special order from their website or Autozone/Adavance Auto/O'Reilly's Auto. $8 plus shipping each). I went with the NGK iridium iX plugs. $7.95 each +tax. Available at most all auto parts stores. NGK iridiums rated to 60,000 miles between changes.
Oil = AMSOIL (only available online or through special dealers - NONE of the typical auto parts stores carries it. $10 p/qt. online + shipping).
I went with Mobile 1 Synthetic Extended PERFORMANCE.
DO NOT CONFUSE WITH Mobile 1 Synthetic!
They are NOT the same.
M1SEP is ~$7 p/qt at most all auto parts stores.
M1SEP is rated at 15,000 miles between changes. AMSOIL is rated at 25,000 miles between changes and when used in conjunction with their oil filter, they guarantee your engine for, I believe, 1,000,000 miles (1 million) at that change interval.
Astounding but I didn't want to wait.
Oil Filter = If going with AMSOIL, go with AMSOIL Oil Filter. I went with K&N HP2009 (HP=High Performance).
ONLY USE 100% SYNTH OIL. (The more hours on the engine without it, the worse it could be to make the switch to 100% synth.)
AIR FILTER! = If going with AMSOIL, go with the full package and get their air filter too. I went with
K&N 332363. Lifetime filter. Clean every oil change by rinsing with H2O, allowing to dry, and then give a light coating of their special air-filter oil. $55. That's right...$55.00! However, since installed, there was an
instant notice in off-the-line 'pep'! (Although, that wasn't my goal.)
I've used only
Premium Unleaded over the past 30 days (since I bought it), I've paid between $3.029 and $3.339 p/gallon. As mentioned at the beginning, I have only gotten a horrible-just horrible-14.4mpg! I do
NOT "get on it" while driving. I DO JAM loud with the myGig Infinity stereo system, though.

epper:
:thk:NEVER BUY ANY GASOLINE WITH ETHANOL!!! It DOES NOT help gas mileage (~20%
DROP in mpg). It DOES NOT run any cleaner than Premium Unleaded. In fact, I can't find definitive answers yet but have found several reports that, it actually burns LESS cleanly, meaning MORE greenhouse gases.)
After the above improvements, I have better performance PLUS I've hit 18.3mpg but seem to maintain about 17.4mpg. Only 3mpg better. EEK. I feel rest assured that my engine will last longer but I would merely break even on the 9,000 mile comparison (3 normal oil changes). I WANT 20MPG IN THE CITY!!! 6mpg would make it all worth while. Especially in the long run.
After
HOURS of research, I have found 3 additional, fairly-affordable things to get that magical "20."
1) in-line airhose vortex creator to better direct the air-flow to the engine. ~$40.
2) Fuel Vaporizer!!!!! :loser1: Simply the best thing you can do to GREATLY increase mileage AND almost completely eliminate ALL greenhouse emissions! If you didn't know, gasoline itself is not flamable. The fumes from the gasoline, however, are. (Remember "flooding" your engine on older cars?) Gasoline is converted to these fumes prior to ignition. The more the liquid is "vaporized," the more efficient the burning of the fuel. (No "flooding" possible because it's all fumes - "vapors".) This should be an easy concept to comprehend. Liquid doesn't burn, it's fumes do! I will install a vaporizer, if it doesn't void the warranty. (I am going to ask the dealer to install it and see if they will keep my warranty valid.) ~$155.
I don't know how much for installation. I can't do it myself as I'm no where close to a mechanic.
3) oxygen sensors. If the flow of air and fuel change, at minimum, you will have to reset the computer by disconnecting battery for 15-20 minutes. But think of what the oxygen sensors do. They analyze the fuel/air mixture coming and going. The computer auto-adjusts itself. If I install a vaporizer, I will also replace the oxygen sensors and then reset the computer to start fresh calculations. I am currently looking into the best oxygen sensor that I can buy or even if there is truly a "good," "better," or "best" brand.
Any suggestions here would help me.
As you see, my quest WILL :SHOCKED:result in 20mpg in the city! (Or my name ain't Orville Reddenbacher!) If I get close to 20mpg, and virtually eliminate greenhouse gases, and get more 'pep', and extend my engine's life expentancy, then hey, I've done all I could. I should be able to stay right at the $500 mark on investments for my engine and the environment. I will certainly keep posting.
Hope this all helped your quest to get above 14mpg like me.
GOOD LUCK!
- NTroGN
selectkc.com