07_Ram

I currently have 3.73 gears on my 4 speed auto dodge with the stock size 265/70 tires. My older rams with the 3.55's and 265/75 tires still got better mpg's than my new truck. 90% of my driving is highway and I rarely tow anything besides my lil fishing boat.
I'm debating on purchasing a set of 3.42's but it's pricey, whats your guys's opinions?

Maybe different tire sizes?

different gear and tire?

geting a six speed is out of the question for me

luke03cr

Get u a set of 285s or sum 305s, a programmer, and drive conservitivly. I get 19mpg all day long with my 35s and programmer turned all the way up

jcismo1

285/75/17 Nitto Dura Grapplers + Smarty Jr = Better everything. Also, drive conservatively, as Luke suggested.

Rednax

1] Stock size tires in closed shoulder highway rib.

2] 3.42 gears and bed cover

3] No mechanical issues (align, tire press, drag, CAC leak, wander)

4] Drive all miles as close to 1300-1500 rpm as possible (Literally).

5] A magic gizmo (Smarty) is optional

07_Ram

3.42's are my next investment, just wondering whether i should go with a diff tire size

.boB

Maybe not the best advice. Wider tires create a wider contact patch. The gives you more traction, but also creates more drag. Like most everything in life, it's a trade off.

A low drag 265 or 255 highway tread with a taller aspect ratio will improve things a little bit, but not a whole lot. A taller tire will change your FDR a bit, but not as much as you might think.

If you have a 2wd truck, it might be cheaper to change the rear end ratio. And you can make a more significant change if you want to. Especially if you already have good tires.

Eat Beef

Bed cover makes NO difference. Proven by Myth Busters.

nvr-enuf

I have put the 285 dura's on my truck and I do not believe they have gained any mpg, they look good and have a high weight rating but I do not think they added mpg.

Before changing the gears, I would suggest doing the PDR cam swap. I have heard that the cam along with smarty can increase the mpg pretty good.

Also, when was the last time you adjusted the valves?

rockcrawler304

I like Myth Busters but they got this one wrong! I've got months of Excel hand calculated mileage data that proves at least MY truck gained with the bed cover on.

Spooler

1.) Smarty
2.) Turbo upgrade
3.) Cam
4.) 60-70hp injector upgrade

This will net you the most mpg depending on how fast you drive. Anything over 70mph and you mpg is going to drop anyway, no matter what you do. Cheapest fix is to slow down. To hold the kind of power above a tranny upgrade will be imperative.

nvr-enuf

One member suggested DDP 35 hp injectors nozzles, they do not "show" them as available but they do offer them. I would think new / better nozzles would help with better spray / atomization. I am thinking the lower HP the better since his goal is strictly fuel economy.