Finally Jumped on the Oil Catch Can Bandwagon

[Caligirl]

I don't think there is a way to tell which valve cover you have unless you pull it off and look at the underside of the casting.

If I recall from a previous thread, you may have posted that your engine is not using any oil at all between changes (I could have that completely wrong and thinking about somebody else). If that is the case, the urgency on any of this stuff definitely gets into the "preventive" mode, versus "fixing" mode.

My belief now is a catch can is a great device for insight into what is going on inside. On an engine that uses oil, it will tell you if you are pumping it out the PCV and back into the intake, which in measurable quantities is not good for anything. If you see large quantities, you know you need to at least get that valve cover pulled and check to see what part number you have.

Yes, that was me...probably driven under 1000 since purchasing at 87k (have to check bill of sale to get exact) and seems to not be losing any.

I'm beginning to wonder if original owner did have it done... if the guy wasn't hurting for money and went in for an oil change and was losing oil on his relatively new engine and they had the service bulletin, it's very possible that he just did it. But see, with the way my mind works I NEED to know lol

 

[Caligirl]

Mine consistently drains 3 oz at every 5,000-mile OCI, so that's the same as yours. Mine came with the updated cover and I disabled AFM about a year after I bought it.

So what does the 3oz consist of? Mostly oil or other gunk? And is there a way to tell, short of having a chemist test it?

 

[wsteele]

Yes, that was me...probably driven under 1000 since purchasing at 87k (have to check bill of sale to get exact) and seems to not be losing any.

I'm beginning to wonder if original owner did have it done... if the guy wasn't hurting for money and went in for an oil change and was losing oil on his relatively new engine and they had the service bulletin, it's very possible that he just did it. But see, with the way my mind works I NEED to know lol

If the oil level hasn't moved on the dipstick in 1000 miles, I doubt you have problems that need addressing right away. A proper catch can will be able to tell you with a little more precision how much oil, if any, you are sending to the intake.

I can't recall exactly, but for certain, I was using at least a qt every 2K miles (for some reason a qt every 1K sticks in my mind) as I had to refrain from topping the oil up for 2K miles to prove to GM my oil consumption was outside their criteria as acceptable (a qt every 2K is a LOT of oil to be "acceptable"). In fairness, when we proved it to them, after the decarbonization process failed to fix the stuck rings, they stepped up with new pistons and rings (and all the other stuff called out in the TSB).

So it sounds like you are pretty far from where I was at 92K miles.

 

[Jason in DLH]

So based on this thread, if I understand it correctly, since I don't know if my Tahoe has the new valve cover, putting in the catch can MAY help me alleviate some of the damage if it's the old one and/or determine if it is (besides taking it off to look-wish they put something on the new ones that is identifiable without taking it apart).

Or do folks who have done the AFM delete/new valve cover STILL get oil/gunk in the can and I won't know from a catch can's contents?

Wish I had more experience with actual work under the hood- I'd take it apart just to look (and replace if needed) even though I'm not showing any signs now at 88k.

Drives my husband nuts thinking I'm borrowing trouble for tomorrow and I prefer to think of it as "prevention-minded" or "forward-thinking". Besides, you'd think the idea that I could tell him "I told you so" if we ever had issues would be enough incentive for him to do it for me now haha

I'm with you and if I ever had issues, it will drive me nuts with the wanting to know if ABC caused XYZ.

I don't think there is a way to tell which valve cover you have unless you pull it off and look at the underside of the casting.

If I recall from a previous thread, you may have posted that your engine is not using any oil at all between changes (I could have that completely wrong and thinking about somebody else). If that is the case, the urgency on any of this stuff definitely gets into the "preventive" mode, versus "fixing" mode.

My belief now is a catch can is a great device for insight into what is going on inside. On an engine that uses oil, it will tell you if you are pumping it out the PCV and back into the intake, which in measurable quantities is not good for anything. If you see large quantities, you know you need to at least get that valve cover pulled and check to see what part number you have.

I’m assuming that is the only way to correctly identify the different valve covers as well. I’ll be devoting quite a bit of research to see if I can figure this out before I go ahead and purchase the new, updated cover and will report back if I find an answer.

 

[Jason in DLH]

So what does the 3oz consist of? Mostly oil or other gunk? And is there a way to tell, short of having a chemist test it?

Water, oil, and fuel. Not sure the proportions though. From what I can tell from my first use of the catch can it looked mostly to be oil.

 

[wsteele]

I’m assuming that is the only way to correctly identify the different valve covers as well. I’ll be devoting quite a bit of research to see if I can figure this out before I go ahead and purchase the new, updated cover and will report back if I find an answer.

I think if I didn't know, I would let the air out of the front tires (I am 6 1" and with that little 1" level, that fender is still kinda high to be leaning over for more than a few minutes), and have at popping that thing off.

For most things, "I just gots to know".

 

[Jason in DLH]

Water, oil, and fuel. Not sure the proportions though. From what I can tell from my first use of the catch can it looked mostly to be oil.

@Caligirl :

I wanted to expand further on this earlier, but didn’t have time.

Your probably asking how water is getting in there. It’s due to climate conditions and/or driving style. Something I learned from @iamdub on this very thread! Short trips allows for condensation to form, so make sure to not repeatedly take short trips. Being in Cali you won’t have to worry about freezing temps and condensation. The same happens with my waterproof camera lenses and camera in the winter. If I bring it inside from freezing temps, there’s a potential for condensation to form inside the lens.

 

[Caligirl]

@Caligirl :

I wanted to expand further on this earlier, but didn’t have time.

Your probably asking how water is getting in there. It’s due to climate conditions and/or driving style. Something I learned from @iamdub on this very thread! Short trips allows for condensation to form, so make sure to not repeatedly take short trips. Being in Cali you won’t have to worry about freezing temps and condensation. The same happens with my waterproof camera lenses and camera in the winter. If I bring it inside from freezing temps, there’s a potential for condensation to form inside the lens.

Haha, all I do is short trips...my "commute" is about 12-15 miles total a day. Trying to figure out how to get my transmission to temp :/ but that's a different subject.

And, I live in the Sierra Foothills where we regularly get into freezing temps for a couple months in the winter. Low 20s to low 30s with frost in the mornings and occasional snow flurries. I have the vehicle in a carport, so definitely subject to varied temperature.

Never had this short of a commute to town (actually why we bought this property was in anticipation of retirement some day, so we didn't have to drive too far to get to a hospital and church and such) so this short driving thing is new to me

 

[George B]

Haha, all I do is short trips...my "commute" is about 12-15 miles total a day. Trying to figure out how to get my transmission to temp :/ but that's a different subject.

And, I live in the Sierra Foothills where we regularly get into freezing temps for a couple months in the winter. Low 20s to low 30s with frost in the mornings and occasional snow flurries. I have the vehicle in a carport, so definitely subject to varied temperature.

Never had this short of a commute to town (actually why we bought this property was in anticipation of retirement some day, so we didn't have to drive too far to get to a hospital and church and such) so this short driving thing is new to me

Just gotta go for a ride sometimes.

 

[Caligirl]

Just gotta go for a ride sometimes.

Luckily, we live an hour away from Yosemite, so when I can convince my husband to get away from his projects at home we go for a drive there.

I notice that when I drive to work it gets up to about a 100 and I'm at work for 3 or 4 hours and it stays little under a 100 when I get back behind the wheel. By the time I drive home which is uphill it's about a 150 - 160. Of course it's still been in the 30s and 40s in the morning, so it's been pretty chilly.

Wonder if I should be warming it up in the morning a little bit before I leave so that maybe by the time I get home it'll be up to temp.