5.3 oil consumption

Cowpie · June 29, 2016

In my previous 2013 1500, my current 2015 2500, and also my 2006 Cadillac 3.6L, I installed PCV catch cans on them. The amount of oil the engines were "using" turned out actually to be "consuming" I have captured virtually the same amount of oil from the PCV line that the oil level dropped. My 3.6L just sucks gobs of oil thru the PCV line. Many folks complain of 1 qt every 1000 miles. In just 240 miles after putting a Elite Engineering E2 catch can on the 3.6L this is what it captured....

Almost 2 oz in just 240 miles. No WOT stuff either, just normal driving. The amount the catch can captures almost mirrors the amount of oil the engine is consuming, therefore the engine is nice and tight and not using any oil at all. It is just sucking it. My 1500 wasn't nearly as bad, but the results were the same. It would "use" about 1/4 qt between oil changes, and that is exactly what the catch can captured in that time frame. Even my 2015 6.0L does the same thing, but not nearly as bad as the other two. So as GM goes along, they seem to be getting better as controlling it.

Problem is, if one just allows this oil "consumption" to continue, it can lead to excessive carbon buildup on piston crowns and lead to sticking rings on pistons. Also will cause some serious intake valve buildup. You just can't shove large amounts of oil into the combustion chamber and expect anything good to come of it.

06pirate · June 29, 2016

2006 Sierra 4x4 5.3 uses about 1/2 quart between oil changes, which I track by the computer monitor.

MaverickZ71 · July 6, 2016

UPDATE: I had the GM-recommended fix of adding the oil deflector in the oilpan/new valve cover with revised pcv orifice/top engine clean done just before my 5-year powertrain warranty ran out. And I started using a Range V8 module.

My LC9 5.3L V8 with AFM no longer uses over a quart of 5W-30 on a 100 mile trip, which it was doing at the time of that 'fix'. I attribute most of that change to the Range V8 module keeping the AFM from kicking in.

But even with that, the truck still uses too much oil, about 4 quarts per year between the oil changes done by the OLM-indicated intervals. This excessive oil usage clogs the rings, forms deposits on the valves, fouls the plugs (resulting in rough idle and MIL light coming on), and will plug up the cats sooner or later.

Subaru and Honda owners have forced class-action suits against their manufacturers for excessive oil usage. I can't believe GM owners haven't done the same, but unfortunately, apparently a lot of them are too busy ordering Dale Earnhardt Jr merchandise to notice they are 3 quarts (or more) low on oil.