I have an 02 Dodge ram 1500 4x4 quad cab with 89k miles. Auto tranny. 4.7l V8

Ok I am getting 9 MPG and have been for the last 4 tank fillups. I have been driving like grandma and not using defrost. I dont get it! I checked and filled the air in my tires to around 55 (Max is 65). I put a new air filter in changed spark plugs. I changed oil again to see if maybe the oil I had was just horrible at friction. I am out of ideas! I did receive a P0601 on my error code but everything I look up is that the PCM will not affect my gas mileage. What else guys! I am STRESSED.

90% of my drive is on a 55 mph highway of 10 miles distance. I should be breaking 15 EASY.


OH YES I just bought the truck and since I bought it I HAVE NOT gotten any better gas mielage than 9 MPG. So this was a problem prior to my purchase. The truck is no longer under the warranty which I don't care I fix my problems anyways. Just lookin for some advice!

There is no check engine light unless they took it out cause it was on lol.

I have been driving my Jeep Cherokee lately and I get about 23 with it. Like I said I am a grandma because when im commuting to work its all about saving money. lol

I have been thinking about buying a chip do you think it would raise it a couple MPG? I really want to drive this Dodge cross country in the summer but wont do it if I cant get 15+ MPG.

 

cant really help ya with why, but a chip isnt gunna get you up to 15 by its self and the cost of intakes and all that that would help are gunna cost as much as just filling up the tank a time or two, also is this hand calculating or just using the overhead

 

I've been seeing 10-12mpg in my truck waay too frequently. I'm @ 50,000 and Im sure no tuneup was performed before I had it (bought it @ 33,000), so it's def time. My wifes AWD Hemi 'Rango sees at least 12.5 around town, 19 on the highway, that kinda chaps my a$$ a little. Plus her truck sounds better, and can put 5 lengths on me quick, lol.

As far as your problem, it seems you've covered anything I would suggest. I'm not exactly a 'granny' when it comes to my driving styles. Ive been relatively easy on it, but I find a reason every now-n-then to lay it down a little

Edit: I just saw Irelands post, and he made a good point. I'm going by my overhead, which isn't exactly acurate. But unfortunately, its pretty close. 26gallons / less than 300 miles per tank = Not Too Good! (I know the actual math equation is backwards, but you get the idea)

 

hand by dividing miles and gallons

Would buying coils help also? What would someone buy to do a typical tuneup? I was hearing something about a leaking plenum gasket? Someone said I may have that... How would I check. I am telling you if I drive like a granny I get like 9-9.5 and if I mess around I get around 8. So somethin gotta change! I love my Dodge and will keep it but just want better gas mileage. Otherwise it will be only when I need to drive it ill drive it lol.

 

not too sure on the plenum gasket, but yeah im getting 11 city and 16-18 highway and i have the 5.7, try normal maintenance, cleaning tb and whatnot changing the rest of the fluid

 

Last time I measured almost got 10 MPH but I drive 20% city and 80% highway every day. About 2 miles city and 11 miles 55 mph highway with no stop signs. Changed plugs and put in a treatment to try and help clean the injectors. What next?

 

This ain't a mod fix, like a tuner or anything. Most MPG mods only get you 1-2 mpg. This is a problem with the truck and with a 4.7 it ain't gonna be plenum gasket.

I would start with a new EGR valve, clean the throttle body and make sure the air filter is in good shape. They are the most common MPG robbers.

Your P0601 is an error within the PCM. The PCM controls just about the whole truck and talks to all your sensors. A faulty PCM would most definitely cause woeful gas mileage. This is possibly due to a short-circuit inside the PCM. Can also be caused by disconnecting the wires/connector from the PCM while the battery is still connected.

I would reset the PCM and see if the situation gets better. If you get the code back or if all the above does not get you better results, then it's probably time for a trip to the dealer to either have the PCM reflashed or replaced...

 

Im also getting horrible gas mileage. 8.4. But I do have 35x12.5 tires with a 5.7 heli quad cab. Would anything help me or am I screwed?

 

I have an 04 QCSB with the 4.7 4x4 and do a lot of city driving and the worst that I have gotten is 11.7 average 14.5 and the best 19.1! I have 80,000 on the dot and a drop in K&N and flowmaster 40series which gave me an extra mpg, but besides tires and stuff I have no performance mods really...

 

Are the QCSB 1500 hemi's supposed to get horrible MPG? im getting 11-12 thats with a new oil change and plugs along with a CAI.