Is Your Gmt-900 Truck Or Suv Using Oil

[music]

I dont think the splash guard has been effective for most folks, which is why I am curious about the valve cover. It makes sense to me, and it's a relatively easy job.

[Folically Challengjed]

I dont think the splash guard has been effective for most folks, which is why I am curious about the valve cover. It makes sense to me, and it's a relatively easy job.

 

As I understand it, the splash cover stops excessive oil from coming up from below, while the valve cover prevents it from coming down from above. Once the piston rings are seized, however, the pistons and rings will have to be replaced. And then, if the valve cover and splash guard haven't been taken care of, you'll be headed down that same path to the next set of stuck rings.

 

FC

[studly]

I was contemplating doing the valve cover upgrade and oil pan shield myself until I read my Chilton's guide on removing the oil pan. It says you have to remove the skid plate, move the steering rack and front 4WD differential out of the way, loosen the bottom tranny bolts, and remove the crossmember just to be able to get to the oil pan. Sheesh! Is that right? [Has anybody done that?] I remember my old 350's where you just removed the oil pan bolts and let'er drop!! (The good old days?!)

The Technical Service Bulletin allocates 5.7 hours for the repair. I asked why it was so much. I was told pretty much what you just wrote. It's a sizeable job to remove the oil pan.

Edited January 25, 2014 by studly

[music]

 

As I understand it, the splash cover stops excessive oil from coming up from below, while the valve cover prevents it from coming down from above. Once the piston rings are seized, however, the pistons and rings will have to be replaced. And then, if the valve cover and splash guard haven't been taken care of, you'll be headed down that same path to the next set of stuck rings.

 

FC

 

Yup, that's pretty much the idea. It's been a while, but when I was keeping up with this a couple of years back, folks that had the deflector installed didn't notice a difference. Maybe it only helps if the pistons haven't already been carbonized?

 

More importantly, and I may be wrong on this, but my understanding is that the deflector is primarily for the return oil during AFM engagement. When the AFM engages, it diverts oil from four lifter pins (that holds them in place), and dumps it into the pan. When AFM is disengaged, then the oil returns through the normal channel (like a non-AFM motor). My understanding may be flawed, but if this is accurate, then disabling the AFM system via the PCM would serve the same purpose, as the oil would never be diverted in the first place.

 

So, my thinking is that a person could disable AFM and install the modified valve cover for the same effect, and get the bonus of clean engine performance (albeit at a slight loss of economy).

[music]

I have a 2008 4WD Suburban with 5.3L.

Here is what they used for my vehicle:

12639759 Deflector

12612350 Gasket

12570427 Cover

 

I had a moment to look those up. The gasket is for the oil pan. Did the valve cover come with a gasket?

[dsmmace]

Its interesting to see the plug with the most deposits came from the same location mine did. My plugs were in worse shape than yours. Although mine were in worse shape with more deposits than yours. What kinds of hours are on your engine?

[Folically Challengjed]

I'm at 115,800 miles, and a bit over 3,300 hours. Lots of hwy miles (V4 Mode).

 

Those plugs had just under 30k miles on them after the new pistons/rings.

 

FC

[strike1st]

Fwiw...I HAD a 2009 silverado...at the third olm oil change around 21k miles it was down 4.5 quarts. No low pressure, no low oil warning....nada. I should've caught it sooner...I had gotten use to engines not burning oil and relying on accurate gauges...I had gotten lazy...never again. Went to nearest dealer...wanted oil consumption test...I only have to change oil once a year so I'd of never finished the test in a reasonable time....they wanted to do the valve cover and then do a test, do the oil pan deflector, then do a test and then the lifters....Only doing each step depending on each oil consumption test coming back bad.

 

I said f that...traded it in at the dealer I bought it from on a 2012 silverado...great truck but got worse mileage than the 2009. Didn't notice issues on the 2012 but it had 13k miles on it and Thursday she got traded in on a 2014 Sierra.

 

Hope GM gets you all taken care of.

[Stex]

Fwiw...I HAD a 2009 silverado...at the third olm oil change around 21k miles it was down 4.5 quarts. No low pressure, no low oil warning....nada. I should've caught it sooner...I had gotten use to engines not burning oil and relying on accurate gauges...I had gotten lazy...never again. Went to nearest dealer...wanted oil consumption test...I only have to change oil once a year so I'd of never finished the test in a reasonable time....they wanted to do the valve cover and then do a test, do the oil pan deflector, then do a test and then the lifters....Only doing each step depending on each oil consumption test coming back bad.

 

I said f that...traded it in at the dealer I bought it from on a 2012 silverado...great truck but got worse mileage than the 2009. Didn't notice issues on the 2012 but it had 13k miles on it and Thursday she got traded in on a 2014 Sierra.

 

Hope GM gets you all taken care of.

 

Do you know the '14s will not have the oil consumption issues? I have been asking service mgrs. but they have no history yet as the '14s are so new???

[strike1st]

 

Do you know the '14s will not have the oil consumption issues? I have been asking service mgrs. but they have no history yet as the '14s are so new???

 

I don't know...at this point I'm hoping GM realized the issues and corrected the mistakes in a new design...if not the next truck will have a blue oval.

[studly]

 

Do you know the '14s will not have the oil consumption issues? I have been asking service mgrs. but they have no history yet as the '14s are so new???

T̶h̶e̶ T̶S̶B̶ i̶n̶d̶i̶c̶a̶t̶e̶s̶ t̶h̶a̶t̶ G̶M̶ s̶t̶a̶r̶t̶e̶d̶ e̶q̶u̶i̶p̶p̶i̶n̶g̶ s̶o̶m̶e̶ m̶o̶t̶o̶r̶s̶ w̶i̶t̶h̶ t̶h̶e̶ f̶i̶x̶e̶s̶ i̶n̶ 2̶0̶0̶9̶ b̶u̶t̶ o̶t̶h̶e̶r̶s̶ u̶p̶ t̶o̶ 2̶0̶1̶1̶ s̶t̶i̶l̶l̶ r̶e̶q̶u̶i̶r̶e̶ t̶h̶e̶ f̶i̶x̶e̶s̶.̶ S̶o̶,̶ i̶f̶ y̶o̶u̶ h̶a̶v̶e̶ a̶ 2̶0̶1̶2̶ o̶r̶ n̶e̶w̶e̶r̶,̶ y̶o̶u̶ p̶r̶o̶b̶a̶b̶l̶y̶ d̶o̶n̶'̶t̶ n̶e̶e̶d̶ t̶o̶ w̶o̶r̶r̶y̶ a̶b̶o̶u̶t̶ t̶h̶i̶s̶ A̶F̶M̶ o̶i̶l̶ c̶o̶n̶s̶u̶m̶p̶t̶i̶o̶n̶ p̶r̶o̶b̶l̶e̶m̶.̶

Statement withdrawn upon further investigation

Edited January 27, 2014 by studly

[MaverickZ71]

The TSB indicates that GM started equipping some motors with the fixes in 2009 but others up to 2011 still require the fixes. So, if you have a 2012 or newer, you probably don't need to worry about this AFM oil consumption problem.

 

I don't have the TSB. How do you tell which ones were supposedly 'fixed' in 2009? Mine was built right at the end of '09 production in Silao, but likes to drink oil . . .

[studly]

I̶t̶ l̶o̶o̶k̶s̶ l̶i̶k̶e̶ t̶h̶e̶ a̶l̶u̶m̶i̶n̶u̶m̶ b̶l̶o̶c̶k̶s̶ g̶o̶t̶ t̶h̶e̶ f̶i̶x̶ i̶n̶ m̶i̶d̶-2̶0̶0̶9̶.̶ ̶ Y̶o̶u̶ h̶a̶v̶e̶ a̶ 4̶x̶4̶.̶ ̶ I̶ d̶o̶n̶'̶t̶ t̶h̶i̶n̶k̶ t̶h̶a̶t̶ h̶a̶s̶ a̶n̶ a̶l̶u̶m̶i̶n̶u̶m̶ b̶l̶o̶c̶k̶.̶

Edited January 27, 2014 by studly

[MaverickZ71]

It looks like the aluminum blocks got the fix in mid-2009. You have a 4x4. I don't think that has an aluminum block.

 

I do have an aluminum-block 5.3L LC9 flex-fuel engine. Would've rather had an iron block non-flex-fuel (without AFM!), but aluminum-block flex-fuel trucks with AFM were all they had around here when I bought it. I believe that I read somewhere that all crew cabs get aluminum blocks to save weight with the thought of getting better fuel mileage. If mine has the 'fixes', which I hope it does, then something else must be wrong, as it drinks about a quart of 5W-30 every 1000 miles with the AFM turned on, and has since it had 7000 miles on it.

[RyanbabZ71]

 

 

Ryan