For the Vehicle Mechanics

[Machingeaneer]

The lifter collapse issues are far more prevalent starting in 2007.5-2008 due to the addition of the AFM cylinder deactivation system. The 99-07 engines did not have those troublesome lifters.

 

[black dawg]

I have a 2006 Silverado, 4.8 engine. 145k miles

Bought it 1.5 years ago in good physical condition. No oil leaks, runs good, clean etc etc

Now it starts tapping pretty hard, never goes away. Take it to one shop and they basically say just let it tap until it breaks

Bring it to dealership and they say it’s likely cam issue. Would be 1100 just to open it up, they recommend just replacing the engine

I take it to another mom and pop shop after that. They tell me it’s cam issues, and also recommend just replacing the engine.

Does this sound right, better/easier to replace a whole motor? The mom and pop wants $5k to do so plus any bad parts found when tearing apart such as say a water pump.

I can’t sell it like it is really, so I’d have to just lose the money I have in it. I think I’d spend a good bit more to find a decent used one again low miles etc etc

Idk what to do. Suggestions?

cam/lifter issues are not uncommon on the ls, have seen both worn rollers on the lifters, and worn lobes causing noises in the 4.8 through 6.0.

Problem with just openining it up to look, is that the cylinder head has to come off to get lifters out. Have seen some that the wear was only on the lifter, and cam was fine, so there is a chance that it could be saved with minimal..ish expense. Most places wont want to do it that way though.

Wont find a used engine with less miles than what you have. 5k is a reasonable price for the job. Atk engine I assume?

 

[sasquatch]

We forgot to ask if anything happened to the engine before the tapping started, like it overheated, was used to tow a trailer across country, or if the oil is changed regularly.

Our youngest is famous for believing modern engines don’t need oil and has ruined more than one by letting the oil level get so low the lifters sing, then topping it off. lol

Nothing happened, it just started tapping. At first it was just kind of an a early morning tap but then it quickly progressed into a 24/7 tap that is much harder. Oil changes, I've only had it for 25k miles but in that time it was changed regularly.

I've tired an oil additive for this issue and it sure has not changed any.

Engine wise, i cant remember exactly what he said, i am suppose to see them Friday when i am off work. I remember him saying its an improved engine that will have a 4 year unlimited mile warranty is all.

Still just seems crazy, I had a 2001 5.3 that i gave away when it had 330k on it and it never had major work done to it. Its still driving but is getting rough.

 

[TaperPin]

Nothing happened, it just started tapping. At first it was just kind of an a early morning tap but then it quickly progressed into a 24/7 tap that is much harder. Oil changes, I've only had it for 25k miles but in that time it was changed regularly.

I've tired an oil additive for this issue and it sure has not changed any.

Engine wise, i cant remember exactly what he said, i am suppose to see them Friday when i am off work. I remember him saying its an improved engine that will have a 4 year unlimited mile warranty is all.

Still just seems crazy, I had a 2001 5.3 that i gave away when it had 330k on it and it never had major work done to it. Its still driving but is getting rough.

That does suck it happened so quickly after you bought it.

 

[Dave Thomas]

With that kind of milage if the camshaft is worn you are better off putting an engine. I've seen it before where the customer only wanted to replace cam and lifters. We refused the job. He went to the dealership to have it done. He was back in our shop a few months later with a rod knock because when the cam tore up it puts metal throughout the engine and eventually wiped out the main bearings.

 

[LCV]

The noise don’t get louder really as I speed up but I can hear it at any speed

At done it’s almost a clink sound from the lower part of motor on drivers side

The last I brought it seems to be pretty reputable from the local area/reviews

The metal shavings concern was exactly what they mentioned as why I should replace the engine over repair what’s there

Sent from my iPhone using Tapatalk Pro

You said it doesn’t get louder. Does it speed up/slow down at all as you change rpm? A bottom end noise should speed up the same rate as the engine rpm, a top end noise should increase at 1/2 the engine rpm. A tap that doesn’t change frequency at all would be new to me.

The injectors on these engines are often loud as well. I would run some kind of injector cleaner or marvel mystery oil through it and see if there’s any change.

Get a long piece of fuel line or similar rubber hose and put one end to your ear and use the other to probe around the exhaust manifold. It should be obvious if you have an exhaust leak.

That being said a decent mechanic should be able to narrow it down further than the people you’ve seen so far. “Cam issue” is pretty vague and unuseful, did any of them elaborate? A lifter/rocker/pushrod etc… are all fixed cheaper than jumping straight to engine replacement. You can buy a tool to cut your oil filter open and check for metal shavings relatively inexpensively and again a decent mechanic probably would have changed the oil and done so already.

 

[Luked]

Those motors as well as the 5.3 were bad for cam and lifters, and also Rings if your consuming oil.
When I worked at the dealer we used to put in a set a week and kept all of the parts in stock.

It might go another 100k it might not go another 100 miles. No way to know.
Most will say an engine swap is easier and also cheaper.
And if it was mine I would be yanking the engine and swapping in another.
Just depends on your budget and if you have the skills.

 

[fmyth]

If it was my truck I'd get an oil analysis before making any decisions.

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[cnelk]

There’s a small screen under the oil sending unit. It’s a bitch to get to and remove but I’ve done it.
They can get plugged and reduce oil pressure which could cause low oil pressure, which could cause lifter noise.