Have a 2009 Silverado with the 5.3 with AFM. Has become a major oil consumer over the last 20k. It has finally become bad enough that the dealer is going to fix it. Currently consuming 1 quart every 1000~1250 miles. They are going to install an AFM oil valve deflector in the oil pan and a revised valve cover with redesigned PCV. This is supposed to cure the problem unless the rings are so crudded up that they have to go back in again and replace the pistons & rings. I'm fine with the new deflector and PCV change but I'd really like to avoid breaking the engine apart if it's at all possible. The engine has had a steady diet of Mobil and QS dino changed in the 3-5k range. Currently has 57k. What are my options for freeing the rings and cleanup, and then additionally should I move to a synthetic over longer intervals or keep short clean-up intervals on conventional? I remember a product called AutoRX used to be pretty popular around here a few years back? Still around or is there something better?
Sludged GM 5.3 oil burner: Need help cleaning up
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Use a low deposit low NOACK synthetic at shorter intervals. These afm engines are hard on oil. Pennzoil Ultra at 5k maybe.
Perhaps a piston soak and idle flush with Kreen, B12 Chemtool, or SeaFoam.
That, and the repairs your doing already, these should clean you up.
That, and the repairs your doing already, these should clean you up.
Well Im guessing your still under warranty since they are fixing it for you, and because of this you would have to stick with a 5w30. So I would recommend PU 5w30 or PP 5w30 for a couple 3K mile OCI. If warranty is not a concern then I would use M1 0w40 and Marvel Mystery Oil (0w40 to combat the MMO thinning). Any of these options should clean up well, then after that continue with synthetic at 5K OCI unless you want to stick with conventional oil, in which case I would use PYB 5w30.
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Originally Posted By: zuluplus30
I'm fine with the new deflector and PCV change but I'd really like to avoid breaking the engine apart if it's at all possible.
Why? I would want them to not only open it up but also to remove all of the sludge, varnish, and carbon--especially while it is under warranty. After that, you could then switch to a synthetic as others have suggested and start with a clean engine instead of one that is "semi" sludged and still requires cleaning AND never really know if it was clean without opening it up anyway. Ideally, if it is that bad it sounds like a prime candidate for a crate engine...
I'm fine with the new deflector and PCV change but I'd really like to avoid breaking the engine apart if it's at all possible.
Why? I would want them to not only open it up but also to remove all of the sludge, varnish, and carbon--especially while it is under warranty. After that, you could then switch to a synthetic as others have suggested and start with a clean engine instead of one that is "semi" sludged and still requires cleaning AND never really know if it was clean without opening it up anyway. Ideally, if it is that bad it sounds like a prime candidate for a crate engine...
This is just my opinion, but if it were mine I probably would clean it up with PU ran with somewhat short OCI.
Then after it is clean I would definitely run GC. GC is great for slowing down oil consumption.
Then after it is clean I would definitely run GC. GC is great for slowing down oil consumption.
A good friend of mine owns an auto shop and said that the best way to fight the oil consumption problem with the 5.L AFM engines is to use Mobil 1. Forget the conventional oil.
What makes you think the 5.3L engine is sludged? If you've been doing 3-5K oil changes, the engine is probably very clean on the inside.
I had a 2008 Silverado with a 5.3L AFM and it used maybe 1.5 quarts in 6K miles.
My new 2013 only has ~18K miles, but last oil change I drained out ~5.5 quarts.
Another thing you can do is to get an ECU re-programmer to disable AFM, this usually does the trick on AFM oil consumers.
What makes you think the 5.3L engine is sludged? If you've been doing 3-5K oil changes, the engine is probably very clean on the inside.
I had a 2008 Silverado with a 5.3L AFM and it used maybe 1.5 quarts in 6K miles.
My new 2013 only has ~18K miles, but last oil change I drained out ~5.5 quarts.
Another thing you can do is to get an ECU re-programmer to disable AFM, this usually does the trick on AFM oil consumers.
An engine that young with those short change intervals should be spotless inside unless coolant has been getting into the oil or something.
1qt every 1000miles or so? That's a lot of oil ...
This is a genuine mechanical issue that needs mechanical attention. No magical elixir, unicorn pea or those mysterious stoddard solvent will fix your issue.
*sorry*
Q.
This is a genuine mechanical issue that needs mechanical attention. No magical elixir, unicorn pea or those mysterious stoddard solvent will fix your issue.
*sorry*
Q.
If they were going to go in and replace the pistons and rings in my engine for free, I would let them.
Originally Posted By: 2010_FX4
Originally Posted By: zuluplus30
I'm fine with the new deflector and PCV change but I'd really like to avoid breaking the engine apart if it's at all possible.
Why? I would want them to not only open it up but also to remove all of the sludge, varnish, and carbon--especially while it is under warranty. After that, you could then switch to a synthetic as others have suggested and start with a clean engine instead of one that is "semi" sludged and still requires cleaning AND never really know if it was clean without opening it up anyway. Ideally, if it is that bad it sounds like a prime candidate for a crate engine...
I guess I'm just less than trustworthy of a dealership tech getting my engine back together properly.
Originally Posted By: zuluplus30
I'm fine with the new deflector and PCV change but I'd really like to avoid breaking the engine apart if it's at all possible.
Why? I would want them to not only open it up but also to remove all of the sludge, varnish, and carbon--especially while it is under warranty. After that, you could then switch to a synthetic as others have suggested and start with a clean engine instead of one that is "semi" sludged and still requires cleaning AND never really know if it was clean without opening it up anyway. Ideally, if it is that bad it sounds like a prime candidate for a crate engine...
I guess I'm just less than trustworthy of a dealership tech getting my engine back together properly.
Originally Posted By: Quest
1qt every 1000miles or so? That's a lot of oil ...
This is a genuine mechanical issue that needs mechanical attention. No magical elixir, unicorn pea or those mysterious stoddard solvent will fix your issue.
*sorry*
Q.
It is a mechanical problem. GM is well aware of that. AFMs inherently burn a little oil. But the early model years suffer from the PCV valve pulling oil into the manifold and the AFM pressure release valve spraying oil into the deactivated cylinders and gumming up the rings. Once the oil control rings are so gummed up it can no longer control it and keeps pulling more into the cylinders. It's a progressive problem that affects a large number of 2007-2010ish 5.3 motors in all of GM's lineup. They obviously are going to fix the defective parts buy I'm concerned they rings are still so gummed up they will need to be replaced too. I'm just not keen on having the engine torn apart and was hoping for suggestions to clean the ring packs back to acceptable.
1qt every 1000miles or so? That's a lot of oil ...
This is a genuine mechanical issue that needs mechanical attention. No magical elixir, unicorn pea or those mysterious stoddard solvent will fix your issue.
*sorry*
Q.
It is a mechanical problem. GM is well aware of that. AFMs inherently burn a little oil. But the early model years suffer from the PCV valve pulling oil into the manifold and the AFM pressure release valve spraying oil into the deactivated cylinders and gumming up the rings. Once the oil control rings are so gummed up it can no longer control it and keeps pulling more into the cylinders. It's a progressive problem that affects a large number of 2007-2010ish 5.3 motors in all of GM's lineup. They obviously are going to fix the defective parts buy I'm concerned they rings are still so gummed up they will need to be replaced too. I'm just not keen on having the engine torn apart and was hoping for suggestions to clean the ring packs back to acceptable.
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Originally Posted By: zuluplus30
Originally Posted By: 2010_FX4
Originally Posted By: zuluplus30
I'm fine with the new deflector and PCV change but I'd really like to avoid breaking the engine apart if it's at all possible.
Why? I would want them to not only open it up but also to remove all of the sludge, varnish, and carbon--especially while it is under warranty. After that, you could then switch to a synthetic as others have suggested and start with a clean engine instead of one that is "semi" sludged and still requires cleaning AND never really know if it was clean without opening it up anyway. Ideally, if it is that bad it sounds like a prime candidate for a crate engine...
I guess I'm just less than trustworthy of a dealership tech getting my engine back together properly.
Zulu - my thought is that you are on the cusp of "you have nothing to lose and everything to gain". If the rings are stuck (which I assume to be the diagnosis) you/they can try the solvent approach like the procedure recommended for the Saturns, but in the end if it is that bad, it would be better to properly clean it. Have they pulled a valve cover to confirm sludge or?
Originally Posted By: 2010_FX4
Originally Posted By: zuluplus30
I'm fine with the new deflector and PCV change but I'd really like to avoid breaking the engine apart if it's at all possible.
Why? I would want them to not only open it up but also to remove all of the sludge, varnish, and carbon--especially while it is under warranty. After that, you could then switch to a synthetic as others have suggested and start with a clean engine instead of one that is "semi" sludged and still requires cleaning AND never really know if it was clean without opening it up anyway. Ideally, if it is that bad it sounds like a prime candidate for a crate engine...
I guess I'm just less than trustworthy of a dealership tech getting my engine back together properly.
Zulu - my thought is that you are on the cusp of "you have nothing to lose and everything to gain". If the rings are stuck (which I assume to be the diagnosis) you/they can try the solvent approach like the procedure recommended for the Saturns, but in the end if it is that bad, it would be better to properly clean it. Have they pulled a valve cover to confirm sludge or?
Originally Posted By: 2010_FX4
Originally Posted By: zuluplus30
Originally Posted By: 2010_FX4
Originally Posted By: zuluplus30
I'm fine with the new deflector and PCV change but I'd really like to avoid breaking the engine apart if it's at all possible.
Why? I would want them to not only open it up but also to remove all of the sludge, varnish, and carbon--especially while it is under warranty. After that, you could then switch to a synthetic as others have suggested and start with a clean engine instead of one that is "semi" sludged and still requires cleaning AND never really know if it was clean without opening it up anyway. Ideally, if it is that bad it sounds like a prime candidate for a crate engine...
I guess I'm just less than trustworthy of a dealership tech getting my engine back together properly.
Zulu - my thought is that you are on the cusp of "you have nothing to lose and everything to gain". If the rings are stuck (which I assume to be the diagnosis) you/they can try the solvent approach like the procedure recommended for the Saturns, but in the end if it is that bad, it would be better to properly clean it. Have they pulled a valve cover to confirm sludge or?
No. The service manager and the shop foreman said the previous repairs were about 50/50 needing new rings and pistons. They won't know until they do the first fix and re-monitor consumption. I can't fathom the heads are sludged with my oci regiment but I have no doubt the ring packs are a mess. It's consumed roughly 17-19 quarts of oil in the last 20k!
Originally Posted By: zuluplus30
Originally Posted By: 2010_FX4
Originally Posted By: zuluplus30
I'm fine with the new deflector and PCV change but I'd really like to avoid breaking the engine apart if it's at all possible.
Why? I would want them to not only open it up but also to remove all of the sludge, varnish, and carbon--especially while it is under warranty. After that, you could then switch to a synthetic as others have suggested and start with a clean engine instead of one that is "semi" sludged and still requires cleaning AND never really know if it was clean without opening it up anyway. Ideally, if it is that bad it sounds like a prime candidate for a crate engine...
I guess I'm just less than trustworthy of a dealership tech getting my engine back together properly.
Zulu - my thought is that you are on the cusp of "you have nothing to lose and everything to gain". If the rings are stuck (which I assume to be the diagnosis) you/they can try the solvent approach like the procedure recommended for the Saturns, but in the end if it is that bad, it would be better to properly clean it. Have they pulled a valve cover to confirm sludge or?
No. The service manager and the shop foreman said the previous repairs were about 50/50 needing new rings and pistons. They won't know until they do the first fix and re-monitor consumption. I can't fathom the heads are sludged with my oci regiment but I have no doubt the ring packs are a mess. It's consumed roughly 17-19 quarts of oil in the last 20k!
I haven't been able to find the PCV valve on my daughter's 2008 Avalanche 5.3L in several years. What PCV system are they changing out for you?
With a picture being worth a 1000 words I thought anyone with the 5.3 oil consumption problem might benefit from seeing the tsb from GM addressing the problem. It also has pictures of the affected components.
AFM OIL USAGE TSB
AFM OIL USAGE TSB
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Originally Posted By: sopususer
With a picture being worth a 1000 words I thought anyone with the 5.3 oil consumption problem might benefit from seeing the tsb from GM addressing the problem. It also has pictures of the affected components.
AFM OIL USAGE TSB
Interesting and the pictures do highlight the issue with clarity. Although, I am not sure I would agree that one of the cylinder photos with the (seemingly) deep(er) vertical scratches is "normal" wear. Normal with a set of stuck rings perhaps... It does make one wonder how long the engine was trialed before accepting it as proven. We looked at a Tahoe and a Suburban (both with AFM) and when I saw they had it (despite the claims that it has improved/corrected), I immediately rejected them as viable vehicles to purchase.
With a picture being worth a 1000 words I thought anyone with the 5.3 oil consumption problem might benefit from seeing the tsb from GM addressing the problem. It also has pictures of the affected components.
AFM OIL USAGE TSB
Interesting and the pictures do highlight the issue with clarity. Although, I am not sure I would agree that one of the cylinder photos with the (seemingly) deep(er) vertical scratches is "normal" wear. Normal with a set of stuck rings perhaps... It does make one wonder how long the engine was trialed before accepting it as proven. We looked at a Tahoe and a Suburban (both with AFM) and when I saw they had it (despite the claims that it has improved/corrected), I immediately rejected them as viable vehicles to purchase.
Originally Posted By: INDYMAC
I haven't been able to find the PCV valve on my daughter's 2008 Avalanche 5.3L in several years. What PCV system are they changing out for you?
See the TSB for a diagram from sopususer. It is integrated into the underside of the left valve cover. The whole valve cover is getting replaced.
+1 for sopususer. I have a copy of that in the glove box for whenever I get the run-around which dealers are great at doing until you show them something in writing.
I haven't been able to find the PCV valve on my daughter's 2008 Avalanche 5.3L in several years. What PCV system are they changing out for you?
See the TSB for a diagram from sopususer. It is integrated into the underside of the left valve cover. The whole valve cover is getting replaced.
+1 for sopususer. I have a copy of that in the glove box for whenever I get the run-around which dealers are great at doing until you show them something in writing.
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