Hey Folks!!

I just got a reasonably nice 2008 RAM 1500 HEMI Big Horn and really like it over the 2004 I had in all respects but fuel mileage!!

It does about the same around town (14-15) but not much better on the interstate (16-17) where the 2004 would get 19-20!!

I found out it has a 3.92:1 rear end which hurts and I disabled the MDS with a tuner thinking it won't help but perhaps I'm wrong??

Would re-activating the MDS system help much me much??

Happy Thanksgiving!!

 

That gear isn't helping at all. My 04 has the 3.55 and it tops 22mpg @ 60mph

 

I realize that the 3.92 gear is gonna cause higher fuel consumption and my '04 was just like yours as long as I stayed at 60 MPH!!

My question is would activating the MDS help the mileage significantly??

BTW.....this truck is much quicker off the line and much more fun to drive than my '04 so the lower fuel mileage ain't that big of a deal !!

 

depending where you live, the winter blend gas is out which causes poor gas mileage, try a higher octane and put the MDS back on

 

What about plugs? Clean throttle body? Air filter? Maybe some sea foam?

 

I get about the same in my '05 with 3" body lift and 33" mud tires. On the highway/autobahn, I used to average about 18 mpg, calculated by hand, if I kept it right around 70 mph. I had DuraTracs on it then, not the Cooper STTs on it now. Around town is horrendous here as it's all stop and go. The longest highway stretch here is about 15 miles, and I rarely get above 65 mph.

As for the MDS, previous banter here on the boards seemed to indicate that it didn't do much in our trucks due to their size, weight, and aerodynamic deficiencies vs. something like the 300. Give it a shot and see what happens.

 

MDS might be good for a few percentage points. There's no good reason to turn it off anyway. How are you determining the mileage?