I'm new to diesel trucks and am doing some leg work on how to improve my fuel mileage and get better performance, not neccessarily speed, out of my truck.

1. Intakes AEM vs. AFE vs. stock vs. anyone -
I've seen the posts, more turbo noise (good), flow restriction codes (bad), etc. Can a good intake help improve fuel consuption/ mileage? Would an exhaust be a better performance mod?

2. Exhaust
Again, are they all about the same? Banks? MBRP? Who is running what and why?

3. Could it be I'm losing fuel mileage "numbers" on my truck because I put bigger tires on it (265/75R16 vs the stock 245/75R16) I drive ~60 miles T/F work and see about 43 miles click off the range meter. What gives?
I was getting high 15- low 16 and rising (hwy) now its clocking low 15s and dropping (more hills terrain here). Can I re-program the tire size change?

4. LBZ mods, why are they so slow to come out? Some companies don't have any (AEM) or very few (Banks). How much different is the LBZ than the LLY, really? Patience....

5. What does egr block and the finger thing do? Anybody?

Truck specs: '06 2500HD LBZ, crew cab, standard bed, Bridgestone Dueler Revo A/T 265/75R16 on stock wheels, fs2500 BPOF, no engine mods yet.

Thanks!

by changing tire size, you are getting 3.8% more distance(mileage) than what your truck tells you. you should reprogram the computer for the bigger tires if you want actual mpg results.
your mpg is off 3.8% also, if not more cause of the extra weight and drag of the tires.
using math, the smaller tire covers a distance of 95.72" for every revolution.
the bigger tire covers a distance of 99.43". a difference of 3.71" for every revolution your tire makes.

i hope my math is right.:o:

leave your intake stock, all your doing is letting in dirty air.