Poor mpg

[eagar95]

I have a 2006 ram 1500 mega cab the heavy half I have all 3/4 ton stuff underneath me with 35.5 mt tires I have a cold air intake with a throttle body spacer and a bulldog tuner. Since I bought the truck I have been getting 9 mpgs or less and maybe 11 or 12 highway. Any suggestions or thoughts on why it's that bad. I figured even with bigger tires it can't be that bad

 

[Jerrybob]

Wow....that's terrible.....so many things contribute to mileage.....including a heavy foot......I don't have big tires but my crew cab...4x4....5.7 Hemi with 3.92 rear get 21mpg highway consistently. I am old.....don't drive real hard.....your mileage sounds really bad.

 

[dhay13]

I think you answered your own question. Bigger (heavier) tires and possibly heavier wheels? That truck is heavy to begin with being a mega cab. Did you have the speedo re-calibrated to match your tire size? If not then your speedo won't be accurate which will skew your MPG calculations.
My guess is the heavy truck and bigger tires are the biggest factor. Having those mods I wonder if you are a little heavy footed? Nothing wrong with that, just have to expect a mileage decrease from it.

I think a new 2006 1500 only got around 14 or so in town IIRC? Probably not a huge stretch to lose that much with the mods and likely higher mileage so lose a little efficiency there

 

[TotallyHucked]

That's probably about right, that's a heavy truck with some heavy tires. I had an '06 Z71 Chevy with 33 mud tires on it and it got 12-14 average. Look up your tires online and see what they weigh, mine were ~77lbs a piece. That rotating mass hits the mileage real bad.

 

[Zoe Saldana]

I have a 2006 ram 1500 mega cab the heavy half I have all 3/4 ton stuff underneath me with 35.5 mt tires I have a cold air intake with a throttle body spacer and a bulldog tuner. Since I bought the truck I have been getting 9 mpgs or less and maybe 11 or 12 highway. Any suggestions or thoughts on why it's that bad. I figured even with bigger tires it can't be that bad

Did you adj the computer for the larger tires?

All the things you did result in bad mpg.

 

[tron67j]

Big truck, big tires, 3/4 stuff underneath (whatever that means). Do you have aftermarket bumpers, running boards, stuff in bed, big hitch sticking out the back, bed rack, etc? All weight that detracts from mileage. You could also have things like alignment, damaged frame, bent rims, or a myriad of things impacting your mileage. If you want high mpg you have the wrong truck. But to increase it return to stock everything. Keep tools and things out of it and drive conservatively.

 

[MADDOG]

I had a 2007 Mega Can with the 5.7 Hemi & 3.73:1 differential gears in it. It was leveled, had a CAI, 35" tires on 17" wheels, etc... Got terrible mileage around town with a bit of an improvement on the highway.

The combination of the larger tires (more weight, more wind resistance) the leveling kit (more wind resistance) and winter fuels really sucked.

With non-blended summer fuel it got a bit better in town & in the highway. I got a programmer, I opened up the exhaust with a single in/dual out Magnaflow muffler & had a custom tune dialed up for it which helped but it was never great in the mileage department.

Small incremental improvements is what you could achieve but big heavy trucks suck fuel and there's not much you can do to significantly improve it.

Good luck.

 

[TotallyHucked]

As said above, the best things you can do are going back to stock size wheels/tires and also get rid of that Bully Dog and get a custom tune for it. Plug in tuners (in my experience anyway) do more harm than good.

 

[mtnrider]

The only thing you can do is go back to stock, but even then it's not going to be great on that truck.

.