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New here just made an account to ask a few questions but I'll stick around for a little while. I have a 12 Silverado 5.3 LC9 114xxx miles. I had cylinder 7 throw a misfire code pulled plug and it was oil fouled. I'm getting the notorious litter noise. I don't know exactly how much oil it is consuming but I would guess at least 2 qts every 2-2500 miles. I guess my question is should I even worry about the lifters going out with that much oil lost and the cyl 7 plug fouling out? Or should I just save my money and put toward a new engine? I don't mind pulling the heads and putting lifters in but if it needs pistons anyway I guess I'm thinking what's the point. 



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I'd try disabling the AFM/DoD system first, then see how badly it still eats the oil.


We still aren't talking new engine territory yet if you ask me. The same engine could be kept if all you had to do was clean up the cylinder walls with a quick drill hone job, clean up the pistons and install new piston rings and have the cylinder heads checked over.

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If you don’t mind doing the work, pulll the heads and look everything over. If all is good you can do as already mentioned and hone with new rings and reassemble. You can do AFM delete if you would like or just replace the stock lifters.


Good time for a water pump and oil pump and you got an engine for another 200-300k.

spend maybe $1000 doing AFM delete and new pumps. 

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  • 4 weeks later...
  • 1 month later...

Wish OP would check in, I have a 12 that is starting to have a rough idle when you pull up to a SS or red light. I parked it before any damage was done, but when you took off from the SS it immediately ran great from there, it's just when you come to a complete stop it idles rough. I'm thinking the Range Tech plug in AFM disabler may be my best option, sure worth 200 bucks to give it a try. Anybody ?

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