Hi all..........new guy with a question. Background on the truck, I am the original owner, of a 2500 Silverado bought new in 2004. 106,000 miles, oil changes every 5000 with Mobil 1 full synthetic on a 6.0 after the 36,000 mile changes from the dealer ran out. The only major problem this truck has ever had was a flywheel which cracked out around most of the bolt pattern, which we caught and replaced before it turned loose. As the son of an mechanic who grew up in a shop, I do most of the minor stuff myself, but I cant run this one down.

For the last 1000 miles or a bit more, this engine has gradually developed a tick which begins after the engine warms up for 5 minutes or so. This tick has is gradually becoming louder and more persistent. Again, I can't put my finger on it, but it sounds like it may be low on the right side and maybe towards the rear of the engine, but it could be elsewhere. Any thoughts or ideas would be greatly appreciated!

 

Perhaps a lazy hydraulic lifter, or carbon on the valves.

Does the truck drive any worse while the ticking is happening? Check engine light on?

It might be just me, but I would probably try flushing the system out with a seafoam treatment. Just put the seafoam in the oil and run until the oil gets nasty, then change it again.

Also, I would suggest changing every 3k instead of 5k. The issue with waiting, is that the oil still gets dirtier and dirtier. I would change it every 3k.

Maybe wait and see what other people say before you try the seafoam in the crankcase.

 

Thanks Nullhead for the quick reply. I am a Seafoam fan as well. The yellow check engine light has started coming on intermittently for the last week. I change filters at 2500 miles, but have no problem switching to a 3K oil change schedule.

 

Typically a Ticking sound comes from only a few Pieces in the Engine. I wont dive into the obvious items as im sure you have already checked. First posting was on spot in my opinion (Lazy Lifter) with the mileage on the vehicle it could be a Lifter. I would reccomend removing Valve covers try a readjusting the valves see what this does for you. If no fix it doesnt take much to replace the lifters. Sea Foam is great but pooring a liquid fix in your engine is only a temp fix. Mobile one oil changes at 5000 is good i wouldnt go to changing oil every 3000 miles that is false info these days. Oils with the close tolerance engines today can go easy 5000 miles (Bottom line dirty oil "black" means carbon deposits) thats when you want to get it out of the engine.

 

Thanks guys. I am with you both on the lifter. In my limited experience, though, when a lifter is getting weak it is prone to rattle on start up and then fade away. This one is doing the opposite. Am I all wet?

 

Possible exhaust manifold leaking?

 

I suppose it's possible that it could be a solenoid of some sort that is ticking. Does it sound like a metallic ticking, or something electrical? Perhaps even a relay.

Could you capture the ticking on video perhaps, and share it here? I'm interested in hearing what it sounds like.

I agree with ChevGuy too. It is possibly a ticking exhaust manifold. It could be any number of things, really.

What if the lifter only ticks when the engine is warm, perhaps it only ticks because the oil is thinner than it is when the engine is cold. So your lifter would be leaking once the oil thins out.

The other thing you can do is use a very long screwdriver and touch different places on the engine and put your ear to the handle and listen. This will work quite like a engine stethoscope. You're listening for where the sound is the loudest, not where you hear the sound. Find where it is loudest.

 

I know the 6.0Ls are bad for manifolds leaking. Is it louder inside the truck or outside?

 

Hmmmmm.......to answer a couple of questions it is louder outside than inside, in fact I cant hear it from inside the cab.............sounds mechanical, not electrical...........I cant tell a bit of difference in how the engine runs whether it is ticking or not.

I blew it out a little yesterday, dumped in a can of seafoam and after a 20 minute warm up ran it at 4500 rpm in 2nd for 5 minutes and pulled over to listen. No noise. Drove it back home normally, pulled into the garage, and guess what.............tick, tick, tick!.....LOL. This morning, no noise on start up, warmed it for 5 minutes to listen, quiet as a mouse. Drove it 10 miles, got out and it was back.

I will put it back on the ramps tomorrow afternoon and crawl around it again then post up..........thank you all for the ideas!

 

Probably not a manifold leaking if you cant hear it inside its usually pretty loud inside