2007 engine does not run like 2006 engine.

[timgco]

Originally Posted by finall

Hey Tomp!

Ok, a different diameter exhaust would definitely account for this sound difference! Good call.

Now, I am curious. How did you find out this difference? Did you measure the pipes? If so, what prompted you to do this? Or did a muffler shop discover this for you on a custom exhaust install? I would sure like to know.

I have been cruising the Internet to see what changed from 06 to 07, but an exhaust change is not mentioned anywhere......

Good call Tomp.

There was a thread on this a while back. My 06 to 07 was a little different. This one rattles (heat shield), but is slightly louder than my 06 was...befor ethe CORSA exhaust that is.

If you are getting a rough idle, it may need an update/ calibration. I'd take it in and have them plug it in. It should be runing rougher than the 06.

[MONSTERMATT]

LEMON

[mdoyle]

I can't believe nobody focused on the 2 liter overfill, that's a hell of a lot of extra oil and could cause hydraulic effects damaging things; like bending the connecting rods for one.

You could also end up with a host of problems in the PVC system and associated emmisions components.

Did you drive it prior to the overfill and notice a difference in sound and performance?

It's going to be an uphill battle since damage from a stupid mistake like that isn't as easy as pointing at a dent and saying, "here's the problem".

Good luck.

[finall]

Good question.

The oil change was done a couple of days (less than 100 miles) by the dealer, prior to us test driving it and buying it. I am not sure if a 100 miles would be enough to damage the engine?

The 06 engine sure pulled stronger and was quieter. I will ask dealer to flash the PCM or whatever, to make sure timing and firing is correct.

[HUMTECH]

Did not know they changed the exhaust diameter. Learn something new everyday i guess

[Rico001]

Originally Posted by MONSTERMATT

LEMON

Hey Matt awhile since we have seen you here.
Have you got a new Hummer yet?
~Richard

[tomp]

http://www.*******club.com/forum/viewtopic.php?f=3&t=6125&st=0&sk=t&sd=a&hilit=exha ust

[finall]

Hey Tomp,

Thanks for the link! Usefull info. Basically confirms that the late 07 exhaust is really an 08 exhaust. That may explain the growl I am hearing versus the 06.

Anyone have an 07 and 08 H2, and do they sound different or the same?

[finall]

FINAL SOLUTION:

Ok, our 07 SE SUV came back from dealer's shop, and they say that it sounds "normal".

To compare, they brought out a brand new 07 SUT SE for us to test, and it does sound the same idling and during a test drive. Same vibration stopped at idle, when you touch the tires. More vibration off the front right tire than the rest. Same vibration, most pronounced at 1500 rpm and light load when driving.

I did not realize that the 06 was so much quieter and smoother!! The larger diameter pipes on the 07 create quite a roar. The 07's are WAY WAY rougher than the 06s. They apparently "improved" the vehicle. DUh?

On the positive, it gets about 1L/100km better gas mileage with the larger pipes.(= about 2mpg?)

Learn something new everyday with these vehicles!