I have a VanAiken box with 4in exhaust, low restriction muffler, no cat, AFE intake---question I get about 18.5 to 19 best case MPG with a clean air filter. I did not see any improvement in MPG when I put the VanAiken box on. Now with fuel as expensive as it is I would like to get more MPG with a different box or programmer, HP gains would be nice but MPG is the top concern. My 02 Duramax ran a Lot more HP, lift and larger tires and got 23 on the highway. Any suggestions?

 

are you going by hand calculated figures? Are you running stock tire size? What gear ratio do u have? I am not familar w/ the box you have. I didnt see much increase in MPG w/ my ez either, but i also jumped from a 265 to a 315 around the same time.

 

Try the Rokktech crankshaft sensor or the tone wheel mod. Do a search for 'crankshaft sensor' in the 3rd Gen Performance section. Lots of reading.

MikeyB

 

You won't see any mileage increase with the Van Aaken box. That box increases hp by lengthening the fueling duration cycle. I have the VA3.2 and love it. While it runs a bit hot, if I drive easy I havn't seen any decrease in mileage and usually get about 18-19 city and 22 hwy.

 

I picked up about three MPG when I went to the quad race box and usually run on the 100 HP setting. Also saw a slight increase with the Tone Ring Mod, FWIW.

 

Still got a kitty?

 

Lost my kitty and factory muffler and replaced it with a glass packed muffler from a local muffler shop. Inexpensive and sounds awesome but not too loud and raspy like a straight pipe. With the mods in my signature, I can easily average over 21 MPG hand calculated.

 

Quad box and crank sensor both helped me a lot I highly sugest both . I went with the tow haul box and was told it was the best for MPG .I still have kitty and stock air box but have been looking at the scotty 5 and killing the cat .

 

my 03 4x4 w/ 4.10's gets consistantly over 20 ... got to love 700+ miles to the tank

 

Just did the tone wheel mod on my truck last week. Gave me about 1-1.5 increase in MPG. Took less then 20 minutes to do and was easy.....

 

Here's the thread with the tone wheel mod.. you have to get a few pages in to find it.

https://www.dieseltruckresource.com/...ad.php?t=71543

 

Thanks---my kitty died and mpg calculations are by hand not the lie o meter. I have used the 215hp Race Programmer on my old Duramax that Quad makes and I picked up almost 3 mpg on that one but also had propane and the Duramaxamizer with a ATS tranny. May try the tow box because I don't want to shell the tranny (converter) as they are pretty fragile.