When GMC/GM/Chevrolet decided to start with a clean slate with their new V8 design they did an amazing job. Starting in 1995 the production of the “LS” style engine began hitting the market, stopping the production of the old reliable 350/5.7L engine in consumer vehicles. But just like everything that is new, there are always a few hick ups, one being the oil consumption issues on nearly all LS based engines.
With our personal experience the early LS style engine have bad PCV valves that suck in too much oil and “coke” the pistons causing oil to bypass and be consumed. What we mean by “coking” of the piston is too much oil bypasses and starts to get burnt and begins to glaze over the piston causing it to not seal properly.
The later LS style engines have problems with the valve cover baffles and Displacement On Demand (DOD) systems.
WHAT WE RECOMMEND
-We start almost all oil consumption issues with de-coking the pistons. While not “technically” difficult it is time consuming, and you have to watch out for what you’re doing. This get the glaze off the pistons and lets them start sealing again.
Next we then fix the problem causing the coking. Early LS engines it is usually the PCV valve that needs replaced, and on later LS engines it is the valve cover baffle and disabling of the DOD that needs done. While disabling the DOD system does void the warranty (most vehicles are out of warranty anyway) it vastly extends the life of the engine with negligible to nearly no downsides.
THE OTHER PROBLEM
Be it obvious, oil consumption causes your engine to run low on oil, which eventually starves it. This causes internal engine damage/harm. If caught early you are usually pretty safe with the engine being ok (not always). In our experience as long as the engine isn’t run dry for too long and the “coke” issue is fixed the engine goes on living a fruitful life. While we can’t guarantee this will fix your issue, it is a worthwhile job to attempt compared to engine replacement.