PCV, or not to PCV?

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gmartin1215

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I have a 2009 5.3 with 150K miles on it.

I grew up with the fact that PCV are regular maintenance items that must be replaced. However, with this engine, the PCV is part of the rocker cover that can't be pulled or screwed out.

According to this TSB, any model built before Feb 1, 2011, has an older style rocker cover prone to more oil consumption and should be replaced with an updated one if that symptom exists. Given that cut-over date, I likely have the older style cover. Is there a way to check without removing the cover to see where the orifice is located?

My engine burns a little oil (what engine doesn't?), but it's not excessive to where I have to keep adding a lot to it. However, I do get a little bit of burnt oil in the exhaust (not really noticeable unless you are staring at it), but I was attributing that to possibly worn rings. The idle is good, but I wouldn't say it's smooth; the engine shakes a little, but mostly, it's good.

Given the above and age, does it make sense to go ahead and replace the PCV/rocker-cover?

Part of me says, "If ain't broke, don't fix it!" BUT, the other side of me says to "do it," at least for preventative maintenance, and maybe add an oil catch can, too (if those things really work, and the reason I started to get into the PCV research).


What would you do?
 

Dustin Jackson

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When I did my AFM delete (2008 5.3 Tahoe) I put on the new valve covers and since then I lose almost no oil between oil changes.

I personally think that it is important to make sure that you have a properly working PCV system to avoid positive crankcase pressure, positive crankcase pressure can result in oil being forced out of the motor through seals and gaskets but if you have negative crank case pressure then the negative pressure will help keep oil in the motor instead of leaking out.

Another plus side to doing the new valve covers is you get new valve cover gaskets which is another common source of oil loss.

I haven't added a catch can because of where I live I don't really need one but if your climate fosters condensation then it might not be a bad idea.
 

iamdub

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I have a 2009 5.3 with 150K miles on it.

I grew up with the fact that PCV are regular maintenance items that must be replaced. However, with this engine, the PCV is part of the rocker cover that can't be pulled or screwed out.

According to this TSB, any model built before Feb 1, 2011, has an older style rocker cover prone to more oil consumption and should be replaced with an updated one if that symptom exists. Given that cut-over date, I likely have the older style cover. Is there a way to check without removing the cover to see where the orifice is located?

Unless you have service records indicating that it was updated, you can't tell without removing it.


My engine burns a little oil (what engine doesn't?), but it's not excessive to where I have to keep adding a lot to it. However, I do get a little bit of burnt oil in the exhaust (not really noticeable unless you are staring at it), but I was attributing that to possibly worn rings. The idle is good, but I wouldn't say it's smooth; the engine shakes a little, but mostly, it's good.

Given the above and age, does it make sense to go ahead and replace the PCV/rocker-cover?

It is absolutely worth updating the cover if it has not been yet. The engine consuming oil is one thing. The coked-up cylinder(s) leading to stuck rings and accelerated wear, loss of compression and even more oil consumption are what eventually follows. That 30 minutes of labor to at least see if you can mitigate the consumption, however minimal it may be (currently), is certainly justified.


Part of me says, "If ain't broke, don't fix it!"

But, technically, it is "broke" by default if it hasn't been updated. And, in time, it could be more broked.


BUT, the other side of me says to "do it," at least for preventative maintenance, and maybe add an oil catch can, too (if those things really work, and the reason I started to get into the PCV research).

Yay! You're already aware of the need for a catch can. They've been shown time and again to be beneficial on these engines. It seems the only ones that have negative experiences are those in climates that allow the catch can to be flooded with water from condensation. I'm in the Gulf south and mine has straight oil in it. I consistently catch 2-3 ounces every 5,000 miles. That's 2-3 ounces less puddling in my intake manifold and dripping into the rear cylinders.


What would you do?

1. I'd check the valve cover and replace it with the updated one if it hasn't been. This easy task won't be in vain at least for the fact that you can get a good look at the inside of your engine to know if you need to alter your oil change routine (intervals or the oil itself).

2. Invest the ~$20 in a catch can. Don't forget to add the stainless steel scrubber pad if it's not already included.
 
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gmartin1215

gmartin1215

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Unless you have service records indicating that it was updated, you can't tell without removing it.




It is absolutely worth updating the cover if it has not been yet. The engine consuming oil is one thing. The coked-up cylinder(s) leading to stuck rings and accelerated wear, loss of compression and even more oil consumption are what eventually follows. That 30 minutes of labor to at least see if you can mitigate the consumption, however minimal it may be (currently), is certainly justified.




But, technically, it is "broke" by default if it hasn't been updated. And, in time, it could be more broked.




Yay! You're already aware of the need for a catch can. They've been shown time and again to be beneficial on these engines. It seems the only ones that have negative experiences are those in climates that allow the catch can to be flooded with water from condensation. I'm in the Gulf south and mine has straight oil in it. I consistently catch 2-3 ounces every 5,000 miles. That's 2-3 ounces less puddling in my intake manifold and dripping into the rear cylinders.




1. I'd check the valve cover and replace it with the updated one if it hasn't been. This easy task won't be in vain at least for the fact that you can get a good look at the inside of your engine to know if you need to alter your oil change routing (intervals or the oil itself).

2. Invest the ~$20 in a catch can. Don't forget to add the stainless steel scrubber pad if it's not already included.
what catch can do you have?
 
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gmartin1215

gmartin1215

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Unless you have service records indicating that it was updated, you can't tell without removing it.




It is absolutely worth updating the cover if it has not been yet. The engine consuming oil is one thing. The coked-up cylinder(s) leading to stuck rings and accelerated wear, loss of compression and even more oil consumption are what eventually follows. That 30 minutes of labor to at least see if you can mitigate the consumption, however minimal it may be (currently), is certainly justified.




But, technically, it is "broke" by default if it hasn't been updated. And, in time, it could be more broked.




Yay! You're already aware of the need for a catch can. They've been shown time and again to be beneficial on these engines. It seems the only ones that have negative experiences are those in climates that allow the catch can to be flooded with water from condensation. I'm in the Gulf south and mine has straight oil in it. I consistently catch 2-3 ounces every 5,000 miles. That's 2-3 ounces less puddling in my intake manifold and dripping into the rear cylinders.




1. I'd check the valve cover and replace it with the updated one if it hasn't been. This easy task won't be in vain at least for the fact that you can get a good look at the inside of your engine to know if you need to alter your oil change routing (intervals or the oil itself).

2. Invest the ~$20 in a catch can. Don't forget to add the stainless steel scrubber pad if it's not already included.
Alos, why the steel scrubber pad?
 
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gmartin1215

gmartin1215

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Unless you have service records indicating that it was updated, you can't tell without removing it.




It is absolutely worth updating the cover if it has not been yet. The engine consuming oil is one thing. The coked-up cylinder(s) leading to stuck rings and accelerated wear, loss of compression and even more oil consumption are what eventually follows. That 30 minutes of labor to at least see if you can mitigate the consumption, however minimal it may be (currently), is certainly justified.




But, technically, it is "broke" by default if it hasn't been updated. And, in time, it could be more broked.




Yay! You're already aware of the need for a catch can. They've been shown time and again to be beneficial on these engines. It seems the only ones that have negative experiences are those in climates that allow the catch can to be flooded with water from condensation. I'm in the Gulf south and mine has straight oil in it. I consistently catch 2-3 ounces every 5,000 miles. That's 2-3 ounces less puddling in my intake manifold and dripping into the rear cylinders.




1. I'd check the valve cover and replace it with the updated one if it hasn't been. This easy task won't be in vain at least for the fact that you can get a good look at the inside of your engine to know if you need to alter your oil change routing (intervals or the oil itself).

2. Invest the ~$20 in a catch can. Don't forget to add the stainless steel scrubber pad if it's not already included.
Alos, why the steel scrubber pad?
 
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gmartin1215

gmartin1215

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Thanks all!
I ordered the updated rocker cover and the J&L oil catcher (they have a steel mesh built-in).
 

iamdub

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what catch can do you have?

I have a catchcans.com one. A little pricey compared to the ones on Amazon and eBay that are functionally the same, just a different shape. I bought it in a group purchase (on another forum) waaay back in 2010-2011 for a project but never used it. I've bought two of the $15-20 ones off Amazon and see equal results as my $100+ one.
 

iamdub

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Alos, why the steel scrubber pad?

It improves the function of the catch can. I forget the exact amounts, but I consistently drained the same amount of oil from the can at each oil change. After adding the scrub pad, I've consistently drained more, like 1-1.5 ounces more.
 

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