Right side oil leak from the valve cover, leaking onto the exhaust manifold @20000 miles. Fire concern.

- Sterling Heights, MI, USA

Hello, I am writing to you today to inform you of a common and known issue with all GM ls engines that come with active fuel management (afm) or displacement on demand (dod). The lifters in the engine begin to fail somewhere after 40,000 miles - with this particular issue occurring in my own vehicle at just over 61,000 miles. If you were to google "ls dead lifter", "ls lifter failure" or "GM piston slap", the issues arises. I have contacted the Pontiac division at GM to complain about this, but they said that there is "nothing they can do since the engine is no longer covered under their warranty". this is a bs and should be considered a recall if it is a known issue and from what I read on a couple forums, GM has even sent a tsb (technical service bulletin) to their dealers in the past in regards to the issue on this engine for several different GM models. Symptoms and noise on the "dead lifter" issue: You will hear a ticking or knocking sound coming from the engine itself upon start up. Noise tends to be louder on a cold start up and will gradually soften (but not completely go away) once the engine is warm. The ticking or knocking noise continues during idling and revving, speeding up as you press on the accelerator.

- North Hollywood, CA, USA

A tapping noise was heard when the engine was running - whether the car was at idle or moving. The tapping would not cease. The vehicle was taken to the dealer, where they discovered that the #2 valve lifter had collapsed into the camshaft and damaged the camshaft. All 16 lifters, camshaft and associated gaskets were replaced. Had we continued driving the car, more defective lifters would have collapsed, causing the engine to seize. At that point, the engine would have to be replaced. The lifters are defective in all GM cars with this engine (see service bulletin 10-06-01-007D).

- Haddon Heights, NJ, USA