2008 5.3 Engine Oil/Filter + Octane Rating

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iamdub

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...I like the Airaid MIT/AEM dryflow filter combination, but would like to know more about it.

Ask away!


I appreciate everyone and their input in this thread, but I have to give a special thanks to you for all the details and thoughtful responses; I've checked out your build documentation, too, which is a gift to say the least. It's dubious if I will ever undergo a process like yours with my Yukon, but who knows?

:cheers:
 
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CruelJung

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Ask away!




:cheers:
I have quite a few questions, really, and background information to add to the questions.

All of the replies to this thread were great, but I was new to most of these concepts and especially unfamiliar with engine modifications when making the initial post. That being said, I have at least a better understanding now about what factors are at play regarding octane, catch cans, intake air flow, the PCV system, and this updated (2010-14) driver side valve cover.

This is going to be a long reply, but I figure that could be healthy for a discussion board like this and you seem to enjoy the details as well--hopefully others will chime in, too.

I'll try to break everything up into sections for easier navigation and list consolidated questions together at the end (even if it's a bit redundant) since all sections are ultimately related:


AEM Dry Filter: I watched a few video reviews about these filters, most of which focused on performance/sound--which is fine, as I am interested in that also (just not primarily)--and one other very interesting review that focused not only on performance but also filtration quality (which is more important to me, as I want the vehicle to last):

Performance Air Filters - K&N vs AEM vs BMC - DYNO Test:

I imagine the seemingly slight increase of larger particles entering the engine that a paper filter would block are likely innocuous, but I'm curious if you've had any negative experiences related to that since using the filter in your vehicle: engine idle changes, trouble codes, oil pressure, PCM re-learning?


Airaid MIT: Similar to the AEM filter, I've watched several videos and read product reviews for the Airaid MIT. Some people had issues with the throttle body end 'popping off', which seemed to be resolved by simply cleaning the mold release agent from the tube but I would be interested if you had any further insight/experience with that? Also, I read some people experienced a dashboard shake after installing this MIT and both increased oil pressure and engine temperature; did you experience any of this?

The factory intake tube has many strange caverns and channels; have you found these to be at all connected with the PCV issues (i.e., to collect oil/fuel/moisture that makes its way to the intake tube? Did you find any fluids in the stock tube when you removed it and have you found any oil making its way into the MIT?


Oil Catch Can: Initially, when learning about catch cans, I searched for further information and it seemed all was positive except some conflicting opinions about catch cans causing restriction to crankcase ventilation (not many, admittedly)--leading to blown engine/oil seals. As I mentioned earlier in this thread, I do have a small but active oil leak visible at the bell housing (likely rear main seal) to begin with, so that restriction possibility raised a concern for me. Have you had any issues with oil pressure or crankcase ventilation restriction since installing your catch can?

Also, have you found any modifications were needed for the 'clean air' vent on the passenger side, or any other areas of the engine, as part of the catch can install?


Updated Driver Side Valve Cover: (in reference to earlier in this thread) My mechanic did not update the valve cover and I have not been able to confirm any service records indicating this work was done. It looks like I will have to remove the valve cover to know if it's the updated one or not. I don't have any associated trouble codes or blue/white smoke from my exhaust and by taking a piece of paper and applying it to my open oil dipstick tube while the engine is running, my PCV has a negative vacuum (if I am understanding this correctly? the paper is lightly suctioned to the dipstick tube). All of this is to say there's no overt indication to me that my valve cover is causing a problem beyond what an oil catch can would theoretically solve.

If I do change the cover to the updated version, will it be necessary to drill out a larger weep hole (where it already exists right near the PCV valve) and/or drill more holes in the chamber leading to the PCV exit for any sloshed oil to drain from? I have seen many people talk about this, and my concern about updating the cover would be causing a problem where there currently is not one.

Example (edit: I know this guy is a bit confused about the old and updated valve cover differences, but this video explains and shows the drilling modifications the best way I've seen):


Consolidated Questions:

1. Did you experience any negative reactions from the engine or PCM from the AEM/Airaid MIT intake modification?
-shaking, (dashboard) rattling, increased engine temp. or oil pressure, oil in the MIT, etc.?

2. Should I expect a decrease in engine or engine component lifespan for filtering out less particles and potentially increasing heat/pressure in the engine with AEM/Airaid MIT?
-pre-existing oil leak cause for concern?

3. How does this intake modification affect the use of an oil catch can from your personal experience?
-increased likelihood of oil leak or crankcase restriction?
-any other modifications needed to accompany the OCC for it to function optimally (aside from the steel wool you and others suggested)?

4. Is there a good reason not to add an OCC to my engine bay now, if I do not have the updated dr. side valve cover?
-pre-existing oil leak cause for concern?

5. If I do the valve cover update, should I modify the (2010-14) dr. side valve cover or is it okay in its stock form, considering I am not experiencing any overt symptoms of oil burning in my exhaust with my current, unknown valve cover?

Thank you!
 
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iamdub

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Consolidated Questions:

1. Did you experience any negative reactions from the engine or PCM from the AEM/Airaid MIT intake modification?
-shaking, (dashboard) rattling, increased engine temp. or oil pressure, oil in the MIT, etc.?

I did not. The MIT is just a tube that deletes the resonance chambers ("mufflers") and smooths the flow of air into the throttle body. The AEM is just an air filter that seems to be every bit as good in flow and filtration as a stock or stock-style filter. The engine is still sucking air in through the same throttle body. The air is just passing through a smoother, unmuffled "straw" ahead of that throttle body. It is able to flow a little more freely, and I mean a little, resulting in a negligible increase in power at higher RPM. Nothing else is affected and there is no way it could cause negative operational effects if installed properly. The most difference it makes is sound. You simply hear the intake growl sound that is otherwise silenced by the resonator chambers on the stock intake duct.


2. Should I expect a decrease in engine or engine component lifespan for filtering out less particles and potentially increasing heat/pressure in the engine with AEM/Airaid MIT?
-pre-existing oil leak cause for concern?

First off, I'll say that I think the factory air filter is perfectly fine as an air filter. Since installing the Airaid and AEM filter about 70K miles ago, I've had my intake tube off three or four times in ~20K mile intervals. I "white glove test" the inside of the tube and have been quite pleasantly surprised every time by the absence of dust or even an appearance of smudges where I wiped it. Also, my oil is still plenty clean enough at 5,000 miles to be in service longer. I still change it and drain it into a clean container for a friend to run in his Tahoe. The MIT is just a differently-shaped tube. It, and good air filter aren't going to increase heat or pressure in the engine. They're not going to alter oil pressure or affect the operation smoothness of the engine. If there is such a change after installing the MIT, then it is caused by a faulty installation and not from the parts themselves.

The intake and filter, either stock or aftermarket, isn't going to alter a pre-existing oil leak.


3. How does this intake modification affect the use of an oil catch can from your personal experience?
-increased likelihood of oil leak or crankcase restriction?
-any other modifications needed to accompany the OCC for it to function optimally (aside from the steel wool you and others suggested)?

They are not related nor connected, so they don't affect each other. The intake duct DOES have a hose that connects to the PCV nipple on the passenger side valve cover. This is a fresh air INLET for the PCV system. A catch can goes on the nipple on the driver side valve cover that is the OUTLET for the PCV system.

As for the catch can itself, there is no need to modify it other than to increase its filtration efficiency and, if it doesn't come with one, adding that scrubber pad is a cheap and effective way to do so.


4. Is there a good reason not to add an OCC to my engine bay now, if I do not have the updated dr. side valve cover?
-pre-existing oil leak cause for concern?

Not having the updated valve cover makes an OCC more necessary. The updated valve cover keeps the oil inside the engine. The OCC catches what makes its way out of the engine and stores it in a reservoir where you'll have to drain it. The updated valve cover should be your first line of defense since it keep t the oil inside the engine so the OCC will only have to catch the smaller amount of oil that still gets past the updated valve cover.

A pre-existing oil leak isn't a cause for concern when referring to the updated valve cover or OCC. If this leak you speak of is from the driver side valve cover gasket or bolt grommets, then it can be remedied when you update the valve cover.


5. If I do the valve cover update, should I modify the (2010-14) dr. side valve cover or is it okay in its stock form, considering I am not experiencing any overt symptoms of oil burning in my exhaust with my current, unknown valve cover?

There are no modifications necessary to the valve cover.
 

Plimbob

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Cruel, regarding your comment about a slight amount of oil around the filter, I would check the oil cooler block plate which is above your filter. The gasket is prone to seeping on these with a few miles.
 
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CruelJung

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I did not. The MIT is just a tube that deletes the resonance chambers ("mufflers") and smooths the flow of air into the throttle body. The AEM is just an air filter that seems to be every bit as good in flow and filtration as a stock or stock-style filter. The engine is still sucking air in through the same throttle body. The air is just passing through a smoother, unmuffled "straw" ahead of that throttle body. It is able to flow a little more freely, and I mean a little, resulting in a negligible increase in power at higher RPM. Nothing else is affected and there is no way it could cause negative operational effects if installed properly. The most difference it makes is sound. You simply hear the intake growl sound that is otherwise silenced by the resonator chambers on the stock intake duct.




First off, I'll say that I think the factory air filter is perfectly fine as an air filter. Since installing the Airaid and AEM filter about 70K miles ago, I've had my intake tube off three or four times in ~20K mile intervals. I "white glove test" the inside of the tube and have been quite pleasantly surprised every time by the absence of dust or even an appearance of smudges where I wiped it. Also, my oil is still plenty clean enough at 5,000 miles to be in service longer. I still change it and drain it into a clean container for a friend to run in his Tahoe. The MIT is just a differently-shaped tube. It, and good air filter aren't going to increase heat or pressure in the engine. They're not going to alter oil pressure or affect the operation smoothness of the engine. If there is such a change after installing the MIT, then it is caused by a faulty installation and not from the parts themselves.

The intake and filter, either stock or aftermarket, isn't going to alter a pre-existing oil leak.




They are not related nor connected, so they don't affect each other. The intake duct DOES have a hose that connects to the PCV nipple on the passenger side valve cover. This is a fresh air INLET for the PCV system. A catch can goes on the nipple on the driver side valve cover that is the OUTLET for the PCV system.

As for the catch can itself, there is no need to modify it other than to increase its filtration efficiency and, if it doesn't come with one, adding that scrubber pad is a cheap and effective way to do so.




Not having the updated valve cover makes an OCC more necessary. The updated valve cover keeps the oil inside the engine. The OCC catches what makes its way out of the engine and stores it in a reservoir where you'll have to drain it. The updated valve cover should be your first line of defense since it keep t the oil inside the engine so the OCC will only have to catch the smaller amount of oil that still gets past the updated valve cover.

A pre-existing oil leak isn't a cause for concern when referring to the updated valve cover or OCC. If this leak you speak of is from the driver side valve cover gasket or bolt grommets, then it can be remedied when you update the valve cover.




There are no modifications necessary to the valve cover.
Thanks so much for responding to this late reply. I appreciate the advice and personal experience. I've been holding off on these engine components while trying to absorb as much information as possible, since I'm a novice in these areas, but it hasn't been for a lack of desire to do the work.

It's good to know I don't have to potentially disfigure an OEM part (valve cover) for it to function. Bearing that in mind, I guess I'll start with the OCC and valve cover first. It's probably unnecessarily expensive, compared with cheaper options, but I like the Moroso model #85481--looks sharp and comes with a petcock valve for easy draining.

The oil leak I have is down at the bell housing (rear main seal, seemingly). From the times I've crawled underneath, it doesn't look to be sourced from any higher, but I have read that an oil pressure sensor leak can look like a rear main leak sometimes. At any rate, I think the engine is burning more oil than it's externally leaking, so the result of the valve cover swap and OCC install will be interesting. Between the oil change that started this thread and my most recent last week--4,000 miles--my engine lost a total of 1 quart of oil. I made a 500 mile trip shortly thereafter, with some 'competitive high-speed driving' involved, and I had to put in close to 1/2 quart to bring the proper oil level back after I returned. I'm thinking either my oil leak became worse or my 85-95 speeds sloshed more oil than usual into my PCV hose--probably the latter.

As I move further along with engine bay repairs and upgrades, I'll likely make more organized posts with documentation. Hopefully I haven't been breaking any kind of forum code by resuscitating the thread after so long.

Again, thank you!
 
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CruelJung

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Cruel, regarding your comment about a slight amount of oil around the filter, I would check the oil cooler block plate which is above your filter. The gasket is prone to seeping on these with a few miles.
When the leak was first discovered--before I noticed the oily filter and created this thread--I checked that plate in the hope of it being the problem and not my rear main seal; unfortunately, no leak there.

Also, the leaky oil filter was a one-off. I kept that filter and plan to open it to check for any clogging sometime soon, but I haven't done that yet. No such issue since I've been doing my own oil changes, so I think it either clogged somehow (it was loose when I removed it) or my mechanic's assistant didn't tighten it enough in the previous OCI. I've done two oil changes now with an oversized Amsoil filter and haven't had that problem since, although it's worth noting my mechanic was changing my oil in 6 or 7k mile intervals and this recent, second time I've done it myself was at 4k.
 

iamdub

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Thanks so much for responding to this late reply. I appreciate the advice and personal experience. I've been holding off on these engine components while trying to absorb as much information as possible, since I'm a novice in these areas, but it hasn't been for a lack of desire to do the work.

That's what forums and sharing of info is for!


It's good to know I don't have to potentially disfigure an OEM part (valve cover) for it to function. Bearing that in mind, I guess I'll start with the OCC and valve cover first.

GM realized they had a flawed design in the original cover, updated it and made it a standard part going forward. You only stand to gain by updating yours.


It's probably unnecessarily expensive, compared with cheaper options, but I like the Moroso model #85481--looks sharp and comes with a petcock valve for easy draining.

I agree that the Moroso is expensive when it performs the same function as those that cost 1/10 the price. But, those cheaper options have been known to have sub-par components, such as carbon steel baffles and/or hardware on the inside that would quickly corrode. You can do some research and find "good" cheap ones. But, if your time is more valuable and you have no problem spending the money, you're guaranteed a quality part with that Moroso and it has a bracket and hoses designed specifically to fit your engine.


The oil leak I have is down at the bell housing (rear main seal, seemingly). From the times I've crawled underneath, it doesn't look to be sourced from any higher, but I have read that an oil pressure sensor leak can look like a rear main leak sometimes. At any rate, I think the engine is burning more oil than it's externally leaking, so the result of the valve cover swap and OCC install will be interesting. Between the oil change that started this thread and my most recent last week--4,000 miles--my engine lost a total of 1 quart of oil. I made a 500 mile trip shortly thereafter, with some 'competitive high-speed driving' involved, and I had to put in close to 1/2 quart to bring the proper oil level back after I returned. I'm thinking either my oil leak became worse or my 85-95 speeds sloshed more oil than usual into my PCV hose--probably the latter.

That's a considerable amount to burn and it burning more during that 500-mile trip kinda rules out that it's simply leaking out. With your engine having AFM deleted and it still burning that much oil- yes, you definitely need to make some changes. That updated cover and OCC should certainly be your first steps. I'd venture to recommend the upper engine soak just to be on the safe side.


As I move further along with engine bay repairs and upgrades, I'll likely make more organized posts with documentation. Hopefully I haven't been breaking any kind of forum code by resuscitating the thread after so long.

Again, thank you!

Absolutely! We like build/project threads. Even if yours isn't much of a build, it's still a great way to document and share your progress and results.
 

avalonandl

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I will throw my hat in the ring on Wix filters are great. I dont care for Amsoil but thats just me. The synthecis today are so good its hard to go wrong with any major brand. Mobil, Valvloine, Pennzoil etc.

Only brand I dis is Royal Purple and STP
 

Plimbob

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Did you check the oil level sensor on the block on the passenger side of the engine. I had to change mine out about 80K ago and based on the oil around the area it had been leaking a bit when I changed it. If it was leaking much it could make one think it may be a main.

Just a thought.
 

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