[Matterdaddy]

I have a 2013 GMC sierra 1500 SLT 5.3L 4x4. Bought it used when it had 65000k on it through the local GM dealership (who must have changed the oil as the oil life was reset and the oil looked mint). I've put just over 5000k on it since I bought it and the engine started knocking back in October. Thought it was just piston slap as the noise seemed to go away once the coolant got up to temperature (and wasn't throwing codes) , but I ended up taking it back to the dealership twice for a diagnosis. First time I had it in they (dealership) said they couldn't hear the knock. The second time I brought it in for the same issue, I brought a video of the engine knocking and showed it to the shop foreman. He's basically going to completely rebuild the bottom end of the motor and anything else that looks damaged as the truck still has quite a bit of powertrain warranty. He says the knock is coming from the bottom of the engine, but isn't quite sure what it is. Also, I drove it about 64km the other day and it seemed like the oil pressure was decreasing bit by bit (as in 26-30 PSI). No loss in power and the oil level is more that 3/4 full on the dipstick, but I'm kinda scared to drive it now until the dealership gets all the rebuild parts in.

Here's a video of it knocking away on cold start. Can't be regular piston slap as it takes quite awhile for the knock to get quieter.

What do guys think? Rod bearing? Scored cylinder walls?

 

[056.0]

Wow she is not happy. I'd almost think bearings

 

[bazar01]

Do you know what oil was used?
These trucks have a strong bottom end though.
Their weak point is the valve train.

 

[j cat]

these engines with the use of the wrong oil will have oil passageways restricted .. must use Dexos GM approved engine oil or this engine will fail .. also use the AFM delete widget plugged in the the OBDII connector to prevent engine failures .

dealership will not rebuild engine they will have a contractor repair do it . dealership will pull engine and install engine .

good luck .. I would Dump it after the FIX !!!!!!!!

 

[Matterdaddy]

these engines with the use of the wrong oil will have oil passageways restricted .. must use Dexos GM approved engine oil or this engine will fail .. also use the AFM delete widget plugged in the the OBDII connector to prevent engine failures .

dealership will not rebuild engine they will have a contractor repair do it . dealership will pull engine and install engine .

good luck .. I would Dump it after the FIX !!!!!!!!

Dealership called me today. The parts are in. So yes, they will be doing the rebuild. If the rebuild doesn't fix anything long term, I'll know in the short term. That's usually how rebuilds pan out. In which case, I'll still have powertrain. If the engine blows up after the rebuild, I'll be getting a brand new crate engine under warranty. As far as the engine oil that was put into the truck before I bought it? No idea. Should have been dexos 5w30. Like I said before, the oil looked mint when I bought the truck and I haven't driven the truck over 6000km. I'd hate to sell this truck though. The guy that had it before me put some money into it. Custom grill, custom rims, mudder tires and a 4 inch lift. Black truck with a white diamond leather interior. Hard to find.

 

[j cat]

the as you say complete rebuild by dealership not gonna do it .. they will just fiddle around with the valve train components ...top end only, not the crankshaft pistons bearings etc......

the cost for rebuild complete job is about $7K USD ,,,,,,,,,,,,,,,canadian probably 10K...
post back how bad it worked out . how long to do the deal .

 

[Matterdaddy]

the as you say complete rebuild by dealership not gonna do it .. they will just fiddle around with the valve train components ...top end only, not the crankshaft pistons bearings etc......

the cost for rebuild complete job is about $7K USD ,,,,,,,,,,,,,,,canadian probably 10K...
post back how bad it worked out . how long to do the deal .

They ordered new pistons, bearings, seals, gaskets, and a new crankshaft. I'm assuming they wouldn't be ordering bottom end engine components if they weren't going to working on the bottom end. Its on my copy of the work order. I talked to the service center foreman. Told me he was going to replace all of the rod bearings and pistons, depending on what the crank looked like and if anything else was damaged. They already told me it was covered under the powertrain warranty.

 

[056.0]

Not all dealers are knuckleheads. Make sure you get a look at the old parts.

 

[Matterdaddy]

Not all dealers are knuckleheads. Make sure you get a look at the old parts.

I'm going to have a good look at everything once they have it apart. If I see damage on the crank, they're replacing the crank. If I see damage anywhere, they're replacing that. If the cylinder walls are scored, they're ordering a whole new engine. I won't take no for an answer. If it takes a bit longer to fix because they need to order more parts, so be it. Probably going to have them test out the oil pump as well. Better to have it fixed properly than to bring it back in a few months later with even more issues.

 

[056.0]

If there's any crank damage, make sure the whole bottom is rebuilt

 

[RayVoy]

Just my 2 cents (and this is coming from 50 years of repairing experience) ............ Don't piss off the Dealership people!!

If you go in demanding to inspect this and having them change that, you better be prepared to show them your Master Mechanic Red Seal to back up your certification.

Because, if you came into my shop, with no knowledge, and started questioning my ability to inspect and diagnosis your problem, be prepared to receive a job that will get you out of my shop as soon as possible.

 

[j cat]

Just my 2 cents (and this is coming from 50 years of repairing experience) ............ Don't piss off the Dealership people!!

If you go in demanding to inspect this and having them change that, you better be prepared to show them your Master Mechanic Red Seal to back up your certification.

Because, if you came into my shop, with no knowledge, and started questioning my ability to inspect and diagnosis your problem, be prepared to receive a job that will get you out of my shop as soon as possible.

RAY do you believe the dealership is gonna do an engine rebuild ? this a Canadian thing ?

 

[RayVoy]

J, I have no idea; I don't even know if my local dealer rebuilds engines.

The OP talks about how his dealer is waiting for parts and that they have arrived; so, I have to agree with him, it appears that his dealer is going to do the rebuild.

And, I don't know where the OP lives, he may be in Canada

 

[Goldie]

Are they going to give you a warranty on the work ?