I've got a new Dodge Ram Quad Cab 4x4 with the 5.2L 318 engine. Its got 120,000 miles and currently only getting 11.5 to 12 MPG and that is mostly highway. It has a K&N filter, and i just replaced cap, rotor, plugs, wires, and oxygen sensors. What can I do to improve this at all? I didn't buy the truck expecting great mileage, but was expecting a little better than this especially on the highway.

kevin

 

Exhaust, chip, <thinks> umm..

 

Unfortunatley I don't think that you are that far off in gas mileage. It has little miles on it and is a 4x4. You don't know if the previous owner may have changed the gears do you? How does she run? What type of Rpms are you running at highway speed say 65-75 mph? Oil change would help some specially if you change to senthetic. You mentioned replacing the O2 sensors you might check the Cat also. Just some questions and observations.

 

That mileage and engine combo is very similar to my Ram.

On my 1994 Ram, I increased my mileage by + 3mpg by doing the following:

(1) I used 2 cans of Chrysler Combustion Chamber Cleaner (in two treatments). I sprayed the stuff into the throttle body with the engine running.

(2) New spark plugs, wires, and dist. cap.

(3) Replaced the O2 sensor (94 only has one)

(4) I poured one bottle of Amsoil engine flush in the cranckase, with the old oil and idled the truck for 20 minutes.

(5) I drained the oil / flush, and replaced it with Amsoil SAE 10w-30 synthetic oil.

(6) I replaced my petroleum gear lube and changed both axles to Amsoil 75w-90 synthetic.

(7) I changed to a 180 t-stat.


This is what I did and the results were dramatic.

In my Dakota, the synthetic oil and gear lube were good for 1.5 to 2 mpg.

Bill,

 

Thanks guys/gals.......
a little more about it. i haven't changed the case oil or axile oil yet, but is on my to do list. I have however changed engine oil to synthetic and added "Restore" engine treatment and have changed tranmission filter and fluid. I've run a bottle of fuel injection cleaner. Truck runs pretty well. It has an aftermarket exhaust on it, but i don't know what it is. Its kind of old so i'm going to replace it this summer to a dynomax ultraflo. I was thinking about replacing the cat while i'm there. Should i stick with an OEM cat or maybe a High Flow cat? As for gears, i couldn't tell you, don't know what its got but on the highway running 70-75 mph, it reads an rpm of around 2200-2400. What is the stock thermostat in these trucks?

also a couple days ago, i was driving.. went in reverse for a about 50 ft. and then when i went into drive and started to take off, it sputtered for a little while kind of like the old carbureated engines would when they would load up. thats the only time it has ever done that. ?????

kevin