DavidGXP

iTrader: (14)

Our fans never reach 100%? Wow!

Nacho SS

iTrader: (4)

Definitely the way to go...just adjust your tune.

DavidGXP

iTrader: (14)

Well, now my car is doing this and it's definitely not pinging! I can hear it while coasting around corners and under real light throttle. I thought I had an exhaust leak at first, but nothing is lose and I couldn't see any black soot around the welds. The sound does not happen all of the time so its been hard to duplicate.

live2ride

Drive just over 25 on a side street with the windows down and ease off the gas until you see it go into 4cyl mode. You will hear it until you go back into 8cyl mode. You can ease on the gas or drop into 3rd which will cause the change back into 8cyl mode and the noise will go away..

BuffaloSS

iTrader: (3)

Mine is getting worse. I'm going to take it back after I get back from vacation and specifically ask that they put it on a rack and put it in gear to hear it. It's embarrassingly loud, so I drive in 3 all the time "in da hood" so it doesn't sound like a POS.

DavidGXP

iTrader: (14)

Your right and its very embracing It is definitely DOD related

DavidGXP

iTrader: (14)

Well that sucks and I guess mine will only get louder too. I have a real nice sounding exhaust and a jacked up sounding motor.

pgbSS

Mine's doing it again as well. It started again about 3-4 weeks after the dealer installed new lifters. I was running mobil1 before the dealer work and the dealer filled with Penzoil after installing the lifters. After it started rattling again I switched back to Mobil1 and it still does it. I don't think GM knows WTF is causing this. While the engine was torn apart they also tested the DOD selenoids which checked out OK. I haven't had a chance to take it back to the dealer again.

BuffaloSS

iTrader: (3)

I wonder if dealers can exchange info on what they have and have not attempted to do to relieve these issues. I'd like for my uncle's shop to see what they've done with yours so that they realize that others have this issue, and what does/not fix the problem. I'm definitely going to complain about it again, just to keep the warranty claim open.

DavidGXP

iTrader: (14)

I really hate to say this but it might be the transmission. Maybe the chain is slapping against the case? Don't ask me how but somethings going on and I think the trans is to blame.

BuffaloSS

iTrader: (3)

Well, two things are for certain. Switching into 3rd when it chatters stops it immediately, and I believe the trans shifts into another gear when DoD deactivates and reverts into 8-cyl mode. It could easily be something in the trans...and someone said the bell housing many, many posts ago. I'm lost at this point.

Count of Monte Carlo

When the engine warms up really good I will not hear it anymore. Like I said changing the lifters will not work as the noise will come back. It's something with the design. Changing the oil does help. GM will quite possibly need to redo the lifter setup if you want the noise gone. Its not hard to think that an unloaded lifter is not going to make some noise. Obviuosly it is not detrimental as the sound dosen't seem to get any louder. I've noticed this at 15K. I now have 22K.

This is not the Transmission doing this. The unloaded lifters are causing this.

DavidGXP

iTrader: (14)

I would like to know if other LS engines with DOD are making any weird noises?

Count of Monte Carlo

There's an idea.

BuffaloSS

iTrader: (3)

What other LSx engines have AFM now besides the G8? Forgive my ignorance when it comes to the LS-series engines...haven't really even been one for specifics.

BuffaloSS

iTrader: (3)

Thanks neil. Might need to hit up one or more of those discussion forums...and/or check out the Holden section here.

GrandMan

I don't get a chatter or a pinging noise. Instead, my GP exhaust note deepens. I only notice it when the windows are down, sunroof is open, stereo is off and I'm going under 30 or so and barely on the throttle. The car has 12,000 miles on it (or so). I hope it's not a sign of bad things to come!

BuffaloSS

iTrader: (3)

The "deepening" of the exhaust note is normal when DoD de/activates. You'll notice the change, even on the highway.

BlueChevyGuy

Mine started the clattering yesterday, for the first time. Exactly like others on this board have described. Coming up to a stop light after reaching 4th gear. (I believe DOD only works in 4th, maybe 3rd? Certainly not 1st or 2nd.) 2006 MC SS, with ~ 15,000 miles. It has been 4,000 miles since my last oil change with Mobil 1. Oil life monitor reads 61% life remaining. I have a 45-mile freeway commute each day, which causes the miles to accumulate without much wear on the oil. Like others have suggested, I'll go ahead and change out the oil and see if it improves.

I did a lot of thinking about this car's DOD feature before purchasing it - - it made me hesitant to pull the trigger because of the lifter technology. But I figured GM *must* have done plenty of research before putting it into a TON of applications, including the Silverado, RIGHT?!?!? I can only hope for GM's sake that the company can address this before thousands more people have the same problem.

I've started to consider getting a G8 (manual, of course!) or GTO....

Count of Monte Carlo

Had my car at the dealer again for some more issues and I had them check out the noise. They confirmed what I was saying. It's working as designed. No issue.