Hi. Im new to the ram forums. I have an 02 ram SCSB SLT 4.7l 1500 4x4 3.55gears 98k miles.
Mods are : 315/70/17 Yokohama Geolanders, cranked torsion bars, vortex replacement muffler, and a polished K&N FIPK kit.
Recent maintinence : bosch platinum plugs, Mobil 1 oil and M1 filter, trans service(flush and filter), Mobil1 diff gear oil, new water pump and new radiator.
Im gettin about 200miles per tank per my odometer. My speedo has NOT been re calliberated for the 35's. The on board fuel economy average calculates about 9 mpg. Is this common for theses trucks. Most of my driving is local and I rarely see over 40mph unless on Int 287 for less than ten miles. On the highway the comp reads an average of 14mpg. Ive thrown no CEL codes



ANY IDEAS?
Thanks
J

 

well first of all, dont go by the overhead...it ranges from 1mpg off to many mpg off!

My friend has an 04 or 05 4.7L QCSB with 80,000 miles....a 6" suspension lift , 22" motometal rims and 36" tires 3.92 gears no intake flomaster exhaust RP oil...this is alot bigger truck than yours, bigger tires and heavier rims...its got the 3.92 not 3.55 so that helps but the added weight of the extra cab and all of that should at least equal out.

He gets 13 in the city and 17 on the highway...either his truck is great or your mileage sucks....and I believe that yours is very low for a SCSB 4.7

 

first off welcome to the DF!.

I was just windreing have you actually done the math to get your fuel milage?.or are you just reliing on the overhead comps numbers?

 

bigger tires + 3.55 gears= pretty bad gas mileage and loss of power.
i would suggest a re-gear since your rarely do any highway driving. 4.56 seems to be the way to go round here. just costs so much dam money!

 

All right, I've got a very similar setup with one major difference. 3.92 gears!!

I get around 12 in the city and 17 on the highway. And I'm recalibrated for this. I would think the big thing is the gears. You are asking too much of the motor to be pushing around 35" tires with 3.55 gears. JMHO.

 

especially with the 4.7L

 

I believe that all of you gentlemen are forgetting one vital thing... "My speedo has NOT been re calliberated for the 35's."
That is going to make a huge difference. The 3.55's will hurt him around town, but on the highway he is golden. If he came from the stock 245x70x17's that come on the truck and now has 315's his speedo is way off!! I have an 05 4.7 QCSB with 285's on it. I just recently bought a SC 3815 tuner and put a performance tune in it and recalibrated the speedo. It used to take me 11.2 miles to get from my house to my fiance's house, and now it takes 13.5. Now that means that about 20% of my miles were not being logged for the distance I was driving. I used to get 11.5-12.5mpg on a good week (hand calc months of fill ups) and now I am getting 14-14.5 in town. And I am driving it a bit harder than I used to because I like the power. lol I used to be lucky if I made it 240 miles before I was at a quarter tank of gas and now my truck is sitting in my driveway with 270 miles on this tank and the needle has just dipped under 1/3. Plus I spent all weekend doing short trips hauling brush and I used it to pull out stumps. So get a tuner and re-cal the speedo and put a performance tune in there!

 

he says in his first post he rarely sees over 40 mph, so ..... ya all he does is around town.

 

hanks for te quik responses. I dont know if gears are in my budget, nu im sure itll help around town.

 

If his speedo hasn't been recalibrated, doesn't that mean that his odometer is off too? Therefore, he is traveling more miles than the odometer says, which if affecting his mpg calculations.