4.7L Gas Mileage

Kgd said:

Just picked up a used 2003 Dak 4x4, quad cab with the 4.7L engine. This thing is a pig on gas. Have read some older threads and seen some people list generic mods ("exhaust, tune, etc.") but am curious as to what specifically I could do to get some better gas mileage. What sort of exhaust mod? What sort of engine tuning? Any help would be appreciated! Newer to the truck world. Not expecting 40mpg but any help would be great.

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Depends on what you mean by PIG.

I get about 16 in town and 19-24 hwy (depending on load and headwind) that's about the highest you'll see out of it. Pulling my camper I get 12.

mods that help. Cold air intake. Bigger throttle body. High flow y pipe (biggest choke in the system) High flow muffler. And a decent tune for mileage.

That's about all you got for mileage options.

If you have any kind of lift on the truck none of that will really make a difference, the drag from the oversized tires and just the lift in general drop mpg.

Still on first tank of gas but based on consumption so far, looking to come somewhere around 10-12mpg. It looks a little lifted, but not anything egregious. Haven't towed anything yet, just driven in the city and on the highway. I live in Texas and the highway speed limits are much higher, so that may have something to do with it but even then, not loving the 10-12mpg range if that's true for me.

Any specific examples of what you listed above (brands, etc.)? Sorry for the dumb naïve questions - learning on the fly here.

Intake I run is the K&N. Exhaust is a mangaflow dual chamber. Its basically a flowmaster 40. And my Y pipe I just cut and installed dual 2.5 in exhaust myself. Personally I recommend taking it to an exhaust shop and tell them what you want. You'll drop about 1k doing it but its worth every penny imo. Sounds good breathes better and if you get a few mpgs out of it great. Can't guarantee you will get better mileage but in my experience so far when coupled with the intake you'll see at least a small improvement. For tuners there's lots of options sct, bully dog, and edge all make tuners around $300 that will have a mileage tune. I took mine and put it in my 2007 ram recently and have yet to drive the dakota far enough to see what I might have lost.

You need to do a basic maintenance tune up, which is oil and filter change and then new spark plugs and engine air filter since you just bought it and used car lots will do nothing if there is any maintenance due. Then, if the MPG is still that poor, start checking the throttle body as the PCV system can gum up the TB, have the O2 sensors checked out for out of spec operation, and then beyond that is fluid changes on the transmission, transfer case, and axles, and then have the driveshafts checked out. All of that I have noticed has caused my MPG to be bad outside of towing and noticed an immediate increase after I fixed the things I listed.