[ctrlz]

AFAIK, the singular advantage of synthetic blends is lower cost. Otherwise synthetic is superior to mineral oil (or blends thereof) regarding shear resistance, high and low temp viscosity, thermal breakdown resistance, and sludge and oxidation resistance.

[zx9rmal]

Originally Posted by iPODFAN11

GM has superseded semi synthetic to full synthetic, so no issues running full synthetic.

That was my understanding as well, based on service adviser and part number on my work order.

[USRobo]

So the label on the Mobile One fully Synthetic says it supports Dexos and overall it is better for the engine.
Only problem is the dealer charged me for the difference in price versus the semi-synthetic and that cost me an additional $60 apprx. What a rip off?

Thanks for all the information

Originally Posted by ctrlz

AFAIK, the singular advantage of synthetic blends is lower cost. Otherwise synthetic is superior to mineral oil (or blends thereof) regarding shear resistance, high and low temp viscosity, thermal breakdown resistance, and sludge and oxidation resistance.

[ST1LE]

Meh, would not choose Mobil One over Amsoil, Royal Purple, or even the recommended GM brand. It isnt what it used to be.

[fastball]

Originally Posted by USRobo

Just got my 1st free oil change from the dealer and they wanted to put in semi synthetic Dextrose oil and told me that the semi synthetic oil with dextrose is what Chevrolet requires in the LT1 engine.

I told them i wanted fully synthetic Mobil One but I had to pay the difference.

What does this engine really require per Chevrolet?

It's Dexos

Dextrose is a cheap, nasty sweetener companies add to processed foods.

[JLSuperfly]

Originally Posted by Mr. Wyndham

Green label = Dexos1, primarily for gasline engines.

Blue label = Dexos2, primarily for diesel engines.

I thought you were talking about Johnnie Walker.

[camaromike77]

Originally Posted by Mr. Wyndham

It requires oil that is 5W-30 weight, and meets Dexos1 requirements. Some Semi-synthentics, or "synthetic blend" meet this requirement.

GM's AC Delco "Dexos" oils meet the requirement.

..........

[dpevans]

GM does recommend 0w40 DexosII when you track your car.

[Mr. Wyndham]

Originally Posted by JLSuperfly

I thought you were talking about Johnnie Walker.

[Elite Engineering]

Be aware of several things when choosing the oil for your GDI engine. A blend has a good amount of conventional oil in the blend, and this will build up valve coking at many times the rate of a good full synthetic. Also, as GDI engines experience a high rate of piston failures due to LSPI (low speed pre ignition) any amount of conventional oil contributes to this as the vapors are combustible. Then we have to look at what a GDI engine experiences that differs from the old port injection engines it replaces. As the fuel never touches the valves, there is no cooling or cleaning taking place so in as little as 5k miles coking is already occurring VS port injection engines having the valves cooled and clean constantly from the detergent fuel. Also, as the fuel is introduced at 2,000-3,000 PSI many times the amount of raw fuel is forced past the rings. This washes down oil from the cylinder walls increasing wear as well as contaminating the engine oil along with the high amount of combustion by-products. These acids, water, fuel, and abrasive particulate matter (many times that of the old port injection engines due to the hard crystalline abrasive make up of the "hard carbon" as some is shed during operation. Look at Amsoil with their new formulation that renders the vapors non combustive eliminating most of the LSPI failures.


These are not the engines of old, and GM has in the past year switched to only full syn oils due to wear and failures caused by the blends. Also, NEVER go more than 500 miles with that first oil change!! Far to many rod bearing failures when the factory fill full of debris and metal is left in longer than this. They changed the Z06 to 500 miles in the owners manual due to this, but still feel most standard engine owners wont drive hard and see failures. You have a lot of differences in learning to care for these engines to get a long trouble free life out of them, and of course our dual valve E2-X systems correct and trap a good deal of this before it can reach the engine oil and contaminate it as this 2 years study shows:


Final results of 2 year study





Here is a brief summary of what was documented in the 2 year testing by one of the Worlds largest Lubrication companies:


The XXXXXX system was tested on the most severe engine on the road toady as far as GDI related issues. The testing was performed on a fleet of new vehicles including GM and others, but they only focused on the results of the Ford Ecoboost engines as they experience the most severe GDI related effects.


First, here is how the testing was performed. Each vehicle has been run through proper break-in and driven over 10k miles to eliminate ring seating variance, etc.


Then the vehicle would be run for app 5-6k miles on their premium full synthetic oil and a sample drawn...this is without our system installed. Then, our system is installed on that same oil fill, no oil change, and then run another 4-5k miles and another sample drawn and at that time oil is drained and changed.


Here are some examples on just viscosity and fuel dilution:


Miles on vehicle: 55060 Ford 3.5L Ecoboost


Miles on oil when sample drawn: 5,943 Fuel dilution: 5.6% Viscosity @40*C: 45.71 Viscosity @100*C: 8.76 (Now, vehicle is driven and sample drawn below)

Miles on oil when sample drawn: 9,411 Fuel dilution: 3.86% Viscosity @40*C: 46.98 Viscosity @100*C: 8.82 (Even AFTER saturation well above the industry 5% threshold where oil is considered "condemned" or no longer able to protect the engine our system was able to not only prevent further fuel dilution and viscosity degradation, but actually IMPROVED each taking the oil that was no longer usable and extending it's ability to protect far longer.


Now, that was the least dramatic result....some were as high as fuel dilution levels of 7% to above 12% by 5k miles (cold start enrichment in cool/cold conditions adds to dilution far quicker) and we were able to bring those levels down even more dramatically, in some cases by as much as 50% less after a few thousand miles WITH our system installed.


Other benefits documented: Average fuel economy increases of 1-3 MPG due to a cleaner burn with the contaminants removed from the PCV vapors as more energy is released with just air and fuel present during the combustion process. This also shows a significant reduction in knock retard as pre-ignition is reduced and combined with a cleaner burn in the combustion chamber, reduces emissions as well as improves fuel economy.


As our system converts the PCV system to full time evacuation and flushing VS part time as the OEM systems come and retains a closed emissions compliant system.


This prevents the stagnant periods of operation when the contaminants and combustion by-products that enter as blow-by and are the primary source of oil contamination and our system greatly reduces this by removing these at all times the engine is running utilizing 2 separate evacuation suction sources, the intake manifold vacuum for when reversion pluses are not canceling it out (during acceleration or hard operation no evacuation suction is present stock), and using the Venturi effect when accelerating or running high RPM/throttle.


On GDI engines (most all Automakers are now 100% GDI) we have the additional benefit of reducing the intake valve coking issue by as much as 85% (we cannot eliminate all as these engines use variable valve events to allow back filling of exhaust gasses back into the port behind the valves to be re-burnt emulating the outdated EGR system/valves of old.


To summarize, the benefits:


Engine life extended to 2-3 times expected life w.out the system installed.


Fuel economy increase of 1-3 MPG average.


Extended oil drain intervals allowing from 50% to 100% longer use of oil reducing pollution from improperly disposed of drain oil.


Reduced tailpipe emissions. As we remove most of the compounds causing a incomplete burn in the combustion process reducing the amount of emissions.


Reduction of intake valve deposits by as much as 85%.


The downside is these MUST be drained and the contents collected disposed of properly as with any drain oil. every 5k miles as a rule (will vary from engine to engine depending on state of piston ring seal to cylinder walls).


We do have a system that never needs to be emptied or service for in excess of 100k miles, but not released yet that could be retrofitted at a later date.


What is in the contents of the system that are removed from the engine crankcase vapors?


Here is a sample after a 2400 mile drain after being spun in a centrifuge to separate all for analysis:




70% was acidic water (the sulfuric acid produced during the combustion process cannot be separated from the water).
23% was raw fuel (GDI engines introduce fuel at well over 2,000 PSI and this pushes many times the amount past the rings of old port injection systems that operated at 45-50 PSI)
and only 7% was actual oil, and it is saturated with abrasive particulate matter.



This other wise would have remained in the crankcase mixing with and contaminating the engine oil, and also contaminating the intake air charge reducing the over efficiency of the engines combustion process.