Are 4:10 better with bigger tires because it takes more to move them?

 

well yea the bigger tires are heavier so the lower gear ratio makes it easier for the truck to turn them...

 

I should have been more clear, it's not hills, but long grades such as mountains. I regularly travel from 2000 feet elevation to 8000 feet. This is where the higher gears hurt. The 4.10's made a big difference. Now my mileage only suffers when I take this trip at speed above 80-85mph, but I have plenty of power. With stock tires, 4.10's actually improved my overall mileage. But once you get this beast up above 2400 rpm for extendedmiles, it shows up on the gas-o-meter!!!

4.10's are still fine for up to 35's but if you are going to pull a trailer with 37's and go over hills and mountains,you will definately learn what downshifting is all about.

The only way around this is to spend lot's of money on power mods, gears, and gas, or get a oil burner!!!You are going to pay one way or another...

 

I get 22 on completley stock truck. 18 in town.

 

I get about 9.5 around town, that is starting it driving for a couple of miles then turning it off. If I actually drive any distance at all, I get about 13. That is with an 07 4X4 all stock. HOWEVER I still would not trade it for anything else...........except a cummins of course!!! Good luck dude!

 

My average is close to 13 with about 60% driving in the city. On the hwy I can get near 18 mpg's, but down here, in Florida everything is pretty flat. I don't know what my gearing is, but I have the 2wd 1500 with stock tires and suspension. I also run with the tuner and the premium tune loaded. I also drive mine pretty hard. I like to feel the power!!!!!

 

This is our second Megacab.

2006 with the 5.9 Cummins;
City 15 MPG
Hwy 20 MPG
Towing a 34 ft. Jayco Eagle Trailer = 10 MPG

2007 with the 6.7 Cummins;
City 14 MPG
Hwy 18 MPG
Towing same trailer again 10 MPG....

Since we are required to turn ours in every year we never really get to the breakin mileage.
Usually we have about 15,000 miles on them.

Soon will be getting a 2008 and hope the mileage goes up a little. But, I'll sacrifice some mileage for the comfort of the MegaCab.

BTW, looks like 2009 will be the last year for the MegaCab. 2010 should be the year of the new Club Cabs in the 2500 & 3500 series that replace the MegaCabs.

Happy trails,

Bill B. (Michigan)
2007 Meagacab 2500 w/CTD
2007 Jayco Eagle 322FKS

 

06 Megacab with hemi and 3.73 rearend, 4wd. I've had my mega for a year now and 10000 miles later I still get a consistent 11.75 mpg with mostly hwy driving and some in town driving. If I rod around a bit it drops it to under 11. the best I ever did was 15, but that was with a stiff tail wind. I live in NE with some small hills and I pull a 8000lbs camper in 3rd gear. I can run 80+ mph down yhe interstate no problem. But I'll only get 7 or 8 mpg going that fast. If I slow down to 60mph then I can get around 9mpg. I've pulled some big hills before and if I just let the cruise set you'll only be going about 45 or 50 by time you hit the top. But if I run it up to 75 or 80 going down hill then i'll still be running 60 or 70 by the top of the next one depending on the grade. All in all I can't complain to much other than the mileage is dissapointing but it is a 6500lbs truck and if I wanted milage I would've bought a frigging toyota or something. I think a 5.7L should be able to get better mileage but on the other hand I'm very satisfied with the way it pulls for only being a 5.7L. So I guess it kind of evens out.

 

My 08 MC Hemi only has about 1700 miles and bigger tires now - 3:73'S - Hemi. I callibrated the speedo and with mostly Hwy miles I average 13.5 driving 70-75mph. Now if I hammer around town I get in the 10-11 range but taking it easy on a FLAT Hwy I can get over 17, down hill like 23 uphill like 12... It has been getting better with every tank and my buddy the Dodge mechanic said the first tank would totally suck, and it did... it will get better as you get to 20K miles, then about another 1mpg overall as you get to 50K. He has an 06 and so far everything he has said has been true. Now I did get the larger tires so I got the superchips to do the speedo andI also do the 91 tune...

LOVE THE TRUCK!