New Duramax

[GreenScape]

Well, I finally got my new truck. I had to wait three weeks to get it, tooooo long. It was delivered last monday and for the most part I am pleased. I traded my almost identical 01 with an 8.1/allison. The old truck seemed to pull just as well as the dmax, but I can tell that the new one doesn't lug as much. Kind of unhappy with mileage so far, 14 mpg first tank with no towing, 10 mpg second tank all towing, working on third and hopefully it will get better. Any thing beats 5-6 mpg with the 8.1. I have been reading posts on this site for a couple of months now and just joined, but if any of the experts out there have any recommendations or advice for me, I would really appreciate it. Thanks in advance.

[pontiac_m18]

GREENSCAPE, FIRST THINGS FIRST, WELCOME TO OUR SITE & may you get all your questions answered quickly & correctly. The only rule I suggest is to not use the c/c for the 1st 500. miles. Other than that,let it go. :D :D :D

[GreenScape]

I forgot to ask if a 4" exhaust really makes that much difference above the stock 3.5" I can't see that .5" would be that drastic. Would just putting on a straight through muffler help?

[JB 2500HD CC]

With 4000 miles on my truck, I really find that throttle pressure can affect milage...and I have a heavy right foot. I have seen as high as 18mpg not towning, running about 75MPH.

[01_Duramax_Dually]

Greenscape
As always...WELCOME to the site!!!

You will find this site extremely helpful. Lots of great people visit here and offer help.

My first couple of tank fulls were kind of low but it gets better. Let the Allison "Learn" a bit and it will set with your driving habits.

I say, as I always have, do the the break in as normal for the first 500, Then change the Allison filter, the rearend lube and the motor oil. After that let that baby fly, Load it up and tow... :D

Worked perfect for me and I have not had any problems.

Congrats again

[bluenote]

Greenscape-

My O1 is the same size as yours, and now that I have a few miles on it, the mileage and performance seem to be increasing. I have started to see 20+ mpg on highway driving and the power seems better. Stick with it and once that beast is broke in, you'll have a winner.