06'-07' trucks w/6spd autos can use a trans go jr. kit just drop the pan ,no need to pull the trans,good for 125 hp,but after that the torque conv clutchs slip,the real problems are gm drops the trany line psi's in 5 and 6th gear,,drive the truck for 10-15,000 miles ,mine really woke up after 15 thos, its as fast as my 02' 2wd crew cab daully with a edge box, and its 4wd cc daully stock,,after 1,000 change your eng oil ,trany external filter[use gm dex6] and rear diff fluid[only use gm grape juice]

Is it the LMM or the LBZ???

Sam

For the allison, the juice makes more power in lower gears where it's proven to take it and softens the power in upper gears where it's proven it has limits..... then the crank sensor and the abs sensors stay in touch looking for slippage and it detunes if slippage is detected- these are some of the safegards I'm referring to.

Although I have a Cummins when people ask about how to wake up their diesel I always tell them the first thing I would do is install a good set of gauges. Boost, trans temp and EGT. Once you have those items you will find that the number of chips is unending. In my experience I think if you increase the amount of air in(AFE is a good intake system) and the size of the exhaust 4"-5" with a less restrictive muffler you will have a good start. IMO

Just leave it stock setup and enjoy. :drink:

I have a 2007 2500HD CC 4x4 with the Duramax / Allison combo. So far, it's a great truck. I think the mileage is getting better and better. I averaged 18MPG towing a SeaDoo (I know, woopety-doo) to AZ and back. Diesel Place dot com is a great resource if you haven't been there. Mine is now making a light random ticking sound at idle sometimes, which freaked me out, but I guess is somewhat normal after reading up on it at Diesel Place.

I would highly recommend an upgraded hitch if you're planning to tow anything sizable. I put a Putnam XDR on the other week.

As far as break-in, I ran it easy for 500 miles, a little harder after that and changed the oil to Amsoil at around 2,000. I don't think Chevy has too many break-in rules other than no towing or hard starts for 500 miles (or something like that).

John

I have an 03 duramax. first is a set of gauges trans upgrade like a transgo or such, i run quadzilla www.quadzilla.com products along with ppe www.pacificp.com I also did the 4" turbo down tube to a 5" exhaust with an aero turbine muffler and 6" tip along with a Mac intake kit. no complaints with this setup and would run with with the street cars around okc. Since then it has some go spray, lift pump, and looking at dual cp3s to fuel the pig.

this is normal, there is a bulletin out on this, it is most noticeable in the left wheel well.... mine does it from time to time.

JH

Thanks for all the advice. I think I will break it in for 10k or so and then look at some mods. Right now it will be a hitch upgrade and get my shell painted to match.
I would like to go to some 20s but dont want to much of a lift on the truck. 3 or 4" might be enough? Cant wait to get the boat behind it. Need to breakin quick so we can tow to Greers Ferry!!!
Quinlan