I'm not sure about the milage I'm getting on my 2500HD. I don't have any mods yet - still on factory size tires and whatever factory gears (I think they're 4.10 if I've understood right). I only pulled 13mpg highway and I just thought that seemed lower than it should be.... Any tips or thoughts?

I plan on cleaning my MAFS and I'm thinking about a TBS.

 

All depends on how you are driving, but that sounds about right. BigTexasChevy has 4.10's in his 1500 with the 5.3 and he is getting around 14 in town.

 

A custom tune helps tremendously on these engines. A TBS and cleaning your MAFS will help you out a lot, as well as an air intake or just a drop-in air filter. You should also consider the free mods. (See "Tips and Tricks for Free Horsepower"). All of these mods will increase you fuel mileage. Also, try lowering or removing your tailgate. It helped me. You can also over-inflate your tires by about 5 psi to lower the amout of rolling resistance.

 

I certainly agree! With a few mods, your truck will be a lot better on gas. Also it will open the 6.0 up some. God I wish I had a 6.0 in mine!

 

I love the 6.0 - it's stronger than an ox and pulls like a mother.

I looked at the CAI's and I don't see the difference between the CAI's and the stock other than the tube is bigger and the box has a bigger opening - you're still pulling the exact same air into the motor.

Another thing I thought of is how much of a difference would it make if I switched it to an electric fan system versus the one on the motor?

 

Summit says it gives you 1-2 MPG... I trust Summit.

 

Don't get it twisted bro, the CAI will open your truck up. It is one of the few aftermarket mods that will give you (noticable) increases in horsepower. The CAI I put on my truck is my favorite mod thus far. Big difference in acceleration and throttle response and it sounds great. Nothing like the sound of a CAI sucking that air!

With electric fans you will also notice a difference. I'm going to be going to electric fans soon and I can't wait. Ask BigTexasChevy, he has them on his truck and it is nice! A little expensive, but worth it in my opinion.

 

I just talked to a buddy of mine... He's got some fans off a WS6 that fit my radiator that he'll sell me for $20... WOO HOO!!!

 

HOLY CRAP! You are going to save hundreds of dollars! I think I'm just going to go to BigTexasChevy's house and steal fans out of his truck while he his sleeping. If I have the time, I'll steal his 4.10's too!

 

Heh, better off stealing the whole damn axle.... Those bearings are a bitch to install!!!