last Monday 2/6/17 the check engine light come on in my 2012 1500 with the 5.3. Went to dealership and they ran the code and said misfire on number one piston and spark plug. So left it there, the next day they called and said the spark plug was covered with oil. So they ended up putting all new pistons and rings in. Chevrolet had a recall out on this. I brought the truck used and has only 40,000 miles. Got the truck back last Thursday and my question is when should I change the oil and filter? The service manager said it will be good till my service light comes on for the next oil change. I'll be hooking to a 6by14' box trailer next weekend to help move my mom.

 

I always change the oil and filter at 4,000 miles no matter what the service light says. I also never had major engine problems.

 

So relating to the problem you started with, we just limped to a dealership near us with a flashing check engine. We've owned our 2012 5.3 Suburban since 98k miles it now has 116k and was serviced for the plugs at 90k. Well, we have a deteriorated plug, oil covered, with cylinder 6 misfire. The dealership (happens to be where we bought it) is telling us we need to replace the engine with one from a wrecking yard. Do you have any insight here, or can you tell me if they mentioned replacing the block to you? Also care to share the cost of your repairs? They aren't in the shop for another two days and we're trying to estimate what the cost is we're looking at....