JohnD17

OK so after driving about 2 dozen trucks I found one to call my own, I picked it up yesterday and I any really excited about . here are the specs : 2007 2500hd Ext. cab 4x4 LT w/78500 miles on it. I know that’s a lot of mile for an 07 but the truck is in great shape. The truck has the 6.0l motor, 4spd auto trans, limited slip, and the last owner got every toy he could. The truck runs and drives great also came with a Linx bed liner and a gooseneck hitch and break controller.

Ok so here are the questions. All the truck I drove were 6.0 autos 03-07 and I noticed that some of the other trucks I drove had more torque off the line then this one. A few it was hard to keep the tires from chirping my truck is not slow but it doesn’t seam as responsive as some and I am not sure why?

I noticed some had dual exhaust in to the muffler and one tail pipe. My truck the exhaust is tied together just after the cats. Not sure if that would effect it. I do not know if the other trucks I drove had any performance modes and I don’t think there is anything wrong with my truck. Just wondering what to check.

I have been working on cars all my life (I’m 32) but this is the newest most electronically controlled vehicle I have ever owned, any advise would be great.
Today I am going to change all the fluids and give it a good cleaning just to establish a bench mark to go by. Thanks to any advice you have.

Mike Sigmond

Nice buy! looks good. Mine has the same exhaust as you described (dual pipes then connect together after the muffler). Mine has about the same mileage and it has lost a little pep over the 6 years I have owned it, not much tho, I can still lite up the tires if I wanted to. Its probably just the way the ECM tuned itself to the old owner or a sensor or 2 may be going bad.

bad2006z71

Damn good looking truck. you should enjoy it.

i have a 1/2 with 6.0 so im going to tell you they are thirsty but good, strong motors. i would suggest getting a custom tune by someone like justin @blackbear performance. he can tune out the Torque management and abuse mode that chevy programs into these trucks.

you have the 4l80 trans which is stout and strong but it does have more parasitic loss compared to eht 4l60 in the 1/2 tons. i would suggest 90-100% TM removal. you can tune for either 87 or 93 octane but you will see more gains out of the 93 octane.

the 6.0's power band is a little higher in the rpm range than the old 350's but the pull very well.

enjoy the new truck

therewolf

Four suggestions-first change out those "100,000 mile Iridium plugs. At 57K mine were ready to melt off the sides of my 6.0L.

Change the transmission filter.

Verify you have a 410 differential gearing. A good acid test is at 60MPH you should be looking at @2700-3000 RPM. If it's about 1000RPM lower at highway speeds, you've got 342 gears, which will give you double the mileage around town and about +3MPG highway over factory, but won't win any serious races.

Change your air filter, they can clog up fast, and you should keep an eye on it.

Nice truck, and best of luck.

JohnD17

Thanks for the info I changed the air filter today but the old one didn't look bad, I will check the rpm's at 60 that’s good to know I know truck is suppose to have 4.10 gears but it's good to check. The Trans filter will be changed soon when I do the Trans service and I didn't think about the plugs so thanks again.

Thanks<O</O

JohnD17

OK today i noticed the RPM's at 60mph are about 2100 i plugged that all into the calculator and assuming in 2wd the transfer case is a 1:1 gear ratio. the rear dose have the 4.10 gears.

Is there a way to clear the ECM so it will program to my driving habits? Will disconnecting the battery do it or do I need a tuner

Mike Sigmond

Yea, disconnecting your battery for 10-15 min will do it or you can pull the fuse too, thats saves some time.

silverado08

Lots of good thoughts are here but none answer the problem to the no low end torque.
The reason is in the computer. The only way to get the power back is to eliminate all torque reduction, chage the power enrichment, and the drive by wire these trucks use have different settings than the past years. In the computer the dtc can be adjusted up to 100% but if the computer doesnt like how its running it will lock itself up and then u must purchase a new computer.
All GM trucks have this problem from 2007 and up.

bad2006z71

Umm, i answered it, Justin @ blackbear performance.

JohnD17

thanks for all the info the computer being the source of the lower power makes a lot of sense don't get me wrong the truck has power I just drove so many of them over the last two weeks and some had more power. I have been driving the truck for a few days now and I am happier now then I was the day I got it. I think I am going to put some 265/75-r16 BFG AT KO tires on it soon i will post before and after pics when i do.