2009 Silverado 5.3L 4x4

[jackd]

I am tuning my son's 2009 Silverado 5.3L Z71 extended cab truck. It is stock for intake and exhaust. It has a 2-1/2" lift and 285/70R17 tires, basically one size over stock. So far, I had to go +5 on the injector slope. I wanted to check with you guys to see if you are getting similar results. Also wondering if the DOD affects the adjustments on these trucks. It doesn't stay in V4 much at all. I thought about just turning it off and leaving it off. What do you think?
Thanks for your help!

[Grumpy_Aero_Guy]

I recommend turning DoD off..... just my preference. Didn't make an IODA of difference in mileage, which is why GM claims it's there in the first place. It probably DOES--- on the EPA cycle in a lab, but not in real life.

THEN, get a good cruise log done, and adjust trims based on that... see Lew's stickies above...

Use DSLogRedux to reduce the log and see what it says/recommends to do.

When you say...."doesn't kick to V4 much at all" ... that's enough during a log to hose up a log. You want a good 2000-2500RPM in V8 for as long as you can hold it to get a log that has sufficient data for a good analysis.

Trim is a function of many things. It's almost impossible to say if "5 is too much" etc., etc.. Believe and react to good data. This assumes, of course, that you are largly stock, which your post seemed to indicate you, indeed, are.

Once the trims are set, then do another log with a few bursts from near stand still at WOT for as long as you legally can, and take a look at WOT AFR and get that adjusted close to an ideal 12.6.

Again, DSLogRedux can hrlp with that too.

If you want to turn the 5.3 into a terror, ping lew and get one of his "enhanced" tunes. I did. Loads of fun, except when Ohio's best are in the neighborhood....if ya know what I mean.

Hope this helps...and... donations always accepted for DSLogRedux

[jackd]

Thank you.