Oil recommendation

[Johnnyringo]

I have a 2005 Envoy (Denali) 2WD and the 5.3L V-8 with 95K miles on it. I bought it about 6 months ago and I am the second owner. I recently had an oil change at the dealership prior to leaving on a 3000 mile trip towing a 22' camping trailer. I happened to check the oil at about the 1/2 point and found it was 2 qts low. I called the dealer and asked what oil they used and was surprised when then said 5W30 synthetic! I had never used oil before (not towing). I checked it again after returning home and it's down another quart.

I'm wondering if something like Pennzoil Hi Mileage might be a better choice?

Comments appreciated.

 

[hockeyman]

Your oil is burning or leaking somewhere. It doesn't matter what brand you go with, they all burn and leak the same way. You need to find out where it's going, and get it fixed.

I use the cheapest 5w30 synthetic blend that I can find. As long as it has the API Certified label on the front.

 

[mrrsm]

(The Numerical Order of what follows is Irrelevant...The Hosing mentioned here is for the I6... so there will be a variation on WHERE the hoses enter or exit the Block to Intake Manifold...but the Principles are identical for your 5.3 V8...

If you Pull out your Oil Dipstick and you can smell gasoline fumes... then your piston rings have become worn enough to allow Gasoline Fumes into your oil pan...losing lubricity...and allowing the thinned down oil to pass the rings on all cylinders and be burned at a much fast rate.)

There are two, small reinforced rubber hoses fitted to this Atlas Engine that serve as the means to recycle Oily-Gassy Vapours created by the "Over-Pressure" made inside of this Engine:

(1) The Lower Crankcase can become over-pressurized due to the Cylinder Blow-By caused from the imperfect Sealing of the Pistons Rings. So these partially burned gasoline vapours right along with whatever oily mist that gets created by the violent action of the Rotating Assembly, Crankshaft, Rods and Pistons are picked up via a small, Rubber Elbow Hose on the outside of the engine via a spout in the block adjacent the centre underside right near the lower Intake manifold where the Rubber Elbowed Hose connects up to the Lower Intake manifold.

It is through that hose that internal Lower Engine Block air laden with Oily-Gassy fumes allows it to be sucked along the air stream coming through the Intake Manifold and thence passing through the Dual or Single Intake Valves of each Cylinder and then down inside each of the cylinders during every Intake Stroke ...to be added with the discreet injections of fuel and NA air and then burned (or re-burned) after the Compression and Power Strokes occur,

(2) The second area that can suffer with Oily-Gassy Fumes is directly under the Valve Cover(s) ...and under there is small, reinforced Rubber Hose that allows fumes from that location to be sucked out from under the Valve Cover(s)... back up inside of the Air Intake Plenum with the Air Stream and thence through the Throttle Body and it too gets handled in exactly the same manner mentioned in paragraph (1) .

The reason for all of this being done is to satisfy the demands of the EPA Clean Air Act and redirect these noxious, combustible and oily fumes back through the Intake Manifold and cause the Engine to Burn these vapours instead of dumping this Polluted Air out into the Environment. If you ever take off your Intake Manifold and look at all the Black Oil inside of the bottom where the manifold and gasket mate with the Intake side of the Engine Head(s)... you will see two of the four possible reasons why Oil Gets Consumed by this engine as a Normal Part of its Operations...just as @hockeyman stressed in the above post that covers all of these (1-4)...including seepage around Valve Cover Gaskets and from the front and rear Crankshaft Seals.

(3) The third reason for this loss is that Oil under "sling" pressure is dousing the walls of each cylinder to lubricate and somewhat cool the Piston & Rings-to Cylinder Mating surfaces... and invariably a very small amount of the stuff remains stuck to the rings and the walls and it gets burned up in small amounts, right along with the combustible EFI Fuel Sprays, or by Carburettors or any other means of fuel delivery using the Natural Aspiration of Air.

There is no proper reference in TIME that is valid here as to how much sooner this happened... because it does not matter whether it takes you Six Months or Six Days to drive the 3,000 Miles between Oil Changes... The Engine will consume the same amount of Oil during BOTH circumstances... But realize that driving a GM Truck or an SUV filled with a bunch of kids asking you, "Are we there yet...?" every five minutes ...right along with Towing a hooked up 22' Trailer...will add additional stress on both the Engine...and The Driver... ;>)

 

[Capote]

These engines are known for burning up oil when driven hard or towing on a long haul. It's pretty normal under those conditions, I wouldn't necessarily assume you've got a leak somewhere. I have no oil leaks and I use up a quart if it happens to be month I do a lot of WOT or drive it hard. In my opinion you're fine man.

And like previously stated, doesn't really matter what brand of oil or if it's synthetic or not, They all burn up pretty much the same. I run Shell T6 Rotella 5W-40 heavy duty diesel synthetic in mine. Good for keeping lifter noise to a lull.

 

[hockeyman]

These engines are known for burning up oil when driven hard or towing on a long haul.

I actually just learned something today. I seriously did not know this, so I stand corrected.

 

[Capote]

I actually just learned something today. I seriously did not know this, so I stand corrected.

 

[xavierny25]

Hold the phone on that I know for a fact my 2008 4.2 voy (with 140k on the dash) burns oil but my brother-in-laws TBSS(with 60k on the dash) we get out what we put in on ever oil change so far. I've made it a habit when I check my oil level to text or call him to do the same. Unless I'm missing something on the biggest differences between the 5.3 and 6.0.
??????

 

[Capote]

D.O.D makes you burn up oil
TBSS's don't have D.O.D.

 

[Mooseman]

DoD (aka: active fuel management) is known to burn oil. As a test, unplug the vacuum sensor on the brake booster to disable DoD. You will get a CEL. See if you oil consumption goes down.

 

[DocBrown]

I use the cheapest 5w30 synthetic blend that I can find. As long as it has the API Certified label on the front.

X2 on that.

Also as said above the DOD 5.3's do use oil. I go through a couple of quarts every time I tow my travel trailer. Just keep up with it.

Interestingly enough last year we took it on a 1500 mile trip. 700 miles from Milwaukee to Gatlinburg, TN. It didn't burn a drop.

BTW, the issue was fixed with the 2009 5.3s.

 

[mrrsm]

During a recent use of GM Top Engine Cleaner on and inside the cylinders of an I6 Engine with the head removed... After dissolving tons of Carbon... I noticed that I could peek down around in between the Pistons and the Cylinder Walls ... And there was enough room to spy on the Top Compression Ring. Even after spraying "Canned Air" in between... I could still see a heavy black sticky layer of Carbon. So after a repeat treatment with the GM TEC... the Ring appeared Shiny and Very Clean. And so it makes me wonder whether doing a treatment like this would break up the "Carbon Superglue" that would hold the rings tight and forbid their expected rebound sealing and "Springyness" resisting the passage of oil up into the Cylinder Head would help with this problem.

 

[HARDTRAILZ]

Get that synthetic crap out of it.

 

[Frazier]

As far as oil recommendations go. GM recommends dexos approved semi synthetic oil in all DOD/AFM engines. I run valvoline max life and wix filters. Never use a cheap or "high flow" oil filter.

As far oil burning goes. It stems from 2 areas. 1. The pcv system. 2 the AFM system. Start by replacing the driver side valve cover with gm part #12570427. Make sure to use the actual GM brand, as aftermarket replacement brands will not have the updated design. 2. Disable the active fuel management system. Then re evaluate your oil burning. It should stop. Sometimes if it has been burning oil long enough then your piston rings could be gunked up. Hopefully that's not the case.

Another thing that can cause oil consumption is a bad valve seal. But try the pcv and afm first. As those are your most common and easiest fixes.

 

[dkvasnicka]

I run Shell T6 Rotella 5W-40 heavy duty diesel synthetic in mine. Good for keeping lifter noise to a lull.

Interesting, how does your 4.2 like the 40 weight? I see that the kinematic viscosity values are relatively high compared to the prescribed 5W-30 oil. I lived under the impression that 5W-40 and 10W-40 oils can potentially lead to insufficient lubrication. But of course lower oil use and quieter engine is a nice thing. I know you live in a climate a bit warmer than Central Europe but at the same time your place doesn't seem to be as hot as Florida or the Middle East or something... I'm asking because I was thinking about trying Mobil 1 ESP 0W-40, which has kinematic viscosity values a bit higher than my current 5W-30 oil but still sits relatively low on the scale of allowed values for 40 oils, i.e. I don't think it would be a problem for me.

When I bought the truck it also had a heavy duty diesel oil in it, Shell Rimula R6 LME 5W-30. It ran fine, subjectively, but it was there for 1.5 yrs and was of course not carrying GM specs. So it went out immediately.

 

[Redbeard]

Some years back I ran across "Bob's the Oil guy" website. He gives a great lessons on the "hows and whys" oil works in engines. It is educational and worth the time to read. https://bobistheoilguy.com/motor-oil-101/. I would strongly suggest reading his articles before changing any weights of oil we run in our engines.

Redbeard
" Never argue with an idiot, he will drag you down to his level and beat you with experience"

 

[Bow_Tied]

I'm running ACDelco filter and Mobil 1 5W30 which goes on sale often enough and I change my own oil to keep costs in check.