Grandpa's Grocery Getter

I have only had my Truck a month 1200KM's,

It shows 19.0 to 23.5 per /100KM's, which is about 10-12 MPG's. I added K&N Kit Series 63, New Tires BFG 275/65/20 stock 20's, less Revolotion's, it is now staying around 19.0 to 20.0 so it got better but not what you guys all claim not even close. This is town/city mixed driving, no Hwy driving as of yet

I was told I need to get my Computor recalibrated because i added the tires went from 31" to 34" is this true. Told it will show a better out come if I do this???



Thanks Guys sure could use some Input on this......

Bob_Mac

The truck hasn't broken in yet and will get better mileage. The bigger tires will result in lower mpgs and yes, you need to recal the computer for the bigger tire size. Do some hand calculations to get a good idea where your at.

Chucko2929

That is really poor fuel economy for that truck.

My truck also just hit 1200 kms and my life time average is 13.5L / 100km. Best has been 12.2L / 100km on a straight highway drive. I have a 2012 FX4, 5.0L with 20" wheels and 3.73 gears. No mods.

I'd definitely talk to the dealer, looks to me like something is off in the computer.

NASSTY

34" load range E tires + 3.55 gears + in town/city driving + speedo not recalibrated = crappy fuel mileage

dave91gt

I have never even seen my 2012 FX4 in the 14's. Rare for my kind of driving. I am as shocked as anybody to get the kind of fuel mileage out of the 5.0. Best I have seen is 22.9 on a 200 mile stretch of road this summer coming back from Myrtle Beach. My daily average is in the 16-17 range. Thats with complete disregard for getting great mileage. Completely stock though with the factory 18" SRA's and 3.73's. The kind of mileage I have been seeing with larger tires on these trucks will have me second guessing going larger when the time comes.

mechanicboy

Considering the lift, big tires(and wheels), speedo not calibrated for the tires,all city driving with a new engine I'd say those numbers are about right. I wouldn't expect more than 13MPG at best in the city with those mods.

Farmboy2012

I got 19 on the 200 mile trip home from the dealership. Truck had 50 miles on it when I bought it. Screw 4x4, 5.0, 3.55.

BUT now that I'm home doing normal driving, I'm around 15-16ish, but that is only because I take my son to DC which is about a 10mile round trip, I would get considerably less MPG if I drove 5 miles or less.

Grandpa's Grocery Getter

The wheels are stock 20's, and the new tires only weigh 5lbs more then the stock one's. Im actually getting better milage now by about 2mpg then when I first got it and it was stock..so I was getting 21-23 per /100KM which is about 10 mpg.......Iam getting now 19.0 -20.3per /100KM with the mods so its better.......but Im not getting 14-16mpg that everyone says they got when there trucks were new....... I was at 21-23 per/100km....10-11mpg....and now adding the K&N Kit I get better and my foot is into it more to hear that growl......lol....well guess duals are next and good hwy trip....But mind you Im in BC MOUNTIAN Country..lol......no flat land around here....lol

Ohhh well I Love my Truck........guess there is always that!...lol

McCarthy

My 2012 5.0 in its first 500km is averaging 15.6L/100km... not even remotely broken it yet either. But i AM taking it quite easy on the throttle until about ~1200KM's. Which sucks because all i want is to hear the 5-oh at full song...

EDIT: This is 65/35 city/highway

blueovelboy

you know some would say your doing no good buy driving it all old farting to brake it in. you need to jump on it and let the motor slow it self down for the first say 500 miles you will set the rings better. lest thats what some say and its worked great fro me so far!