LongBed

First of all, I understand that it takes a while for the money to be made back on the mods. I want a little extra power without sacrificing mpg.
I have already done a 2.5" level kit (procomp) and am about to put tires on. Was thinking either 33x11 or 33x12.5. Will I see a big difference in mpg between the two? Will both be able to fit in the spare spot?

Okay, on to the mod part...
I was thinking cold air intake and mass airflow sensor. What brand of intake do you guys recommend and will the MAF increase mpg?

Thanks

ryanralston07

JLT, C&M, AEM, Airraid, and Roush are all great ones. Look at a gryphon tuner...

shotgun

Welcome to the site. Year? Engine? Wheelbase? Cab?

The lift kit will hurt your MPG, but not a whole lot.

What tires came on the truck originally? Anthing larger will hurt performance and mileage.

Intakes are a waste of money unless you get a tuner with custom tunes (and even then the improvement is very limited). Do the Gotts mod instead (use the search feature to find a post).

If there's nothing wrong with your MAF, why would you replace it?

Instead, change your air filter, fuel filter, plugs, etc.

XPerties

Because he has probably read nonsense about it doing:

...such as the JET MAF which makes such absurd claims.

lariat 04

Worse aerodynamics, larger tires, more hp, and no loss in mpg's?? Kinda sounds like an oxymoron to me. You can't have the best of both worlds, just have to make sacrafices.

60DRB

The best mpg mods ever invented are the least fun. Lighten your foot on the gas pedal, keep tires inflated properly, and coast to the stop signs and red lights. You will never find a more cost efficient method of saving fuel. How boring.

GATORB8

The 12.50s will be minimally worse on mileage because of increased weight and drag, but will give you slightly better traction. IIRC my fullsize spare is a 275/70R18 (33.4 OD) so you should be fine height wise, I think the 12.50 will just stick a little further down ( I don't remember seeing anything below it).

I say skip the intake side (maybe do the Gotts mod and a filter if you want), and definitely do a tuner. You'll want to correct your speedo, odometer, and shift point with the new tires anyways, why not get some power and better shifting out of it too.

LongBed

Here's the proper intro: 2004 5.4L XL, long bed, standard cab, I believe the original tires were 235/75/17's. I have the stock fx4 rims and bf goodriches on it for now. Can't remember the size off of the top of my head. I can get 18 on the freeway if I'm light on the pedal (and I'm often am), and usually get around 16 mixed. I'm an avid hypermiler and am bringing my skill to bear. I know I can't expect to much increase, I guess I'm really just looking for some added performance without sacrificing any more mpg than necessary.

I'm leaning towards the 33x11 because of fender clearance issues under articulation as well as drivability in the snow. I know some people like wider tires in the snow and mud, but I don't. Call me crazy.

I didn't mention, but I was thinking of the gryphon tuner. I already use mid-grade gas, so I'm hoping this will help. I also like the control over shifting and all of the readouts. Will probably throw in a cold air intake to go with it. I noticed K&N wasn't mentioned. Is this for a particular reason? I noticed on the roush website the claimed power gains seemed higher than others (22 hp and 32 ft-lbs). Can anybody independently back this up?

As for the MAF, that's why I asked. Sounded fishy to me.
I got it a tune up as soon as I bought it and have a highly skilled mechanic on top keeping it ship shape. No problems taking the plugs out! 101,000 miles .

As for aerodynamics, what about a net tailgate or a flush camper? I had a friend that got 2-3mpg more consistently in his ranger on the freeway with his tailgate down. Anybody else's two cents? I know a camper costs the same as a lot of gas, but they're useful too!

Wow...that was a lot.

shotgun

By hypermiler, I hope that doesn't mean you shift into neutral when coasting downhill. If your truck is a 4x4, you are risking drive train damage. Check your owner's manual under Roadside Emergencies.

The Gryphon is a good choice, especially if you are running mid-grade (89?) fuel. Bill can write custom tunes for the 89 octane; right now you're justing wasting money.

I would skip the intake and do the Gotts mod. If you still want an intake, DO NOT do it until you have a tuner and custom tunes. You may burn pistons and valves.

Mythbusters did a show (or shows) on tailgates up or down. I think they concluded up is better. Not sure about a camper. Will the decreased drag make up for the increased weight? If you want a cheap way to improve your aerodynamics, get rid of the lift kit.

XPerties

They did 2, this one is the last one and they did more test: