Cadillac Escalade, EXT and ESV Forum - 1999 - 2006 Discussion, Pop or Ping? in Cadillac Escalade Forums; Our '04 Suburban's exhaust (same issue in every big GM ute) pops/pings loudly while the truck is cooling off (normal ...
Our '04 Suburban's exhaust (same issue in every big GM ute) pops/pings loudly while the truck is cooling off (normal though), but also while out driving--this seems to be the main thing people are complaining about. Cruising on the highway and then stop at a toll booth or something and it sounds like you're in the middle of a drive by. This is while the truck's still running, so it's very annoying sometimes....and not an issue our previous mouse-like '02 Avalanche ever had.
Apparenly it's an issue with condensation getting in between the metal layers of the muffler and as it heats up, the moisture somehow makes it pop pretty loudly, like a popcorn popper. It's been a "GM Engineers are working on it" issue for a while now, but the real problem seems to be that they just cheapened the exhaust materials on the newer models, b/c this was not a known problem in the first couple model years of the GMT-800's, to the best of my knowledge.
Only real fix is getting aftermarket exhaust pieces.
If the ping eminates from the engine under acceleration or high load (third gear-half throttle uphill) this could be a slight pre-ignition condition due to low octane fuel usage or too much timing advance. Try filling your (empty) tank with the sunoco 92 premium fuel plus add Chevron Techron fuel injector cleaner to help clean up carbon deposits in the combustion chamber(every 3K miles). I notice a HUGE difference on 92 octane fuel alone!