Piston Slap, Rod Bearing Knock or something else horrible

[Pittdawg]

Just today my engine developed a horrible knokcing/slapping type sound. My mechanic fears the worst. Swapping out my tuned pcm as soon as pcm4less can get me a stock loaner and crossing fingers whatever it is is covered by powertrain warranty. Ugh.

 

[Boricua SS]

judging by your sig, they're going to have raised eyebrows if it is a major issue... when the adjuster came out to look at my truck (first motor that spun a bearing), first thing he did was plug in the OBDII and scanned for the tune, second, he hung around while they tore it down to inspect the parts... i even went as far as to put on my stock intake tubing and air filter so there weren't any questions...

hope it comes out good for you bro... i DEFINITELY know what you're going through right now... i think we all know why

 

[CaptainXL]

Just today my engine developed a horrible knokcing/slapping type sound. My mechanic fears the worst. Swapping out my tuned pcm as soon as pcm4less can get me a stock loaner and crossing fingers whatever it is is covered by powertrain warranty. Ugh.

Make sure they program the stock loaner to the exact same CALID's your VIN number is showing on GM's Tis2Web website (TIS). That way if you take it into the dealership and they scan it there won't be any problems.

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Just today my engine developed a horrible knokcing/slapping type sound. My mechanic fears the worst. Swapping out my tuned pcm as soon as pcm4less can get me a stock loaner and crossing fingers whatever it is is covered by powertrain warranty. Ugh.

Make sure they program the stock loaner to the exact same CALID's your VIN number is showing on GM's Tis2Web website (http://tis2web.service.gm.com/tis2web). That way if you take it into the dealership and they scan it there won't be any problems.

 

[Pittdawg]

Thankfully GM extended me powertrain warranty coverage. Official diagnosis, "Pitted connecting rod bearings. Replace all connecting rod bearings". How does this happen???