You'll never see a local driving gas mileage difference - maybe 0.5% to 1% over a 1,000 mile trip. Run whatever engine oil is recommended or available in the viscosity range for your ambient temperature - as shown in the owners manual.

API designations SK, SJ, SL, SM, then the GM licensing specs for DEXOS (which are SM and SN oils) - all good oils, all just fine for any engine.

DEXOS is not an oil refining specification as such - it's a licensing specification from GM so packagers can market their oils as "meeting GM specifications" - which it ALL did before DEXOS was ever "invented". AMSOIL markets some excellent oils that are not DEXOS licensed but beat the requirements in spades. So does Joe Gibbs Racing - JoeGibbsDriven.

http://www.api.org/certification-pr...a/Files/Certification/Engine-Oil-Diesel/Publications/MOM_GUIDE_ENGLISH_2013.pdf

 

mine says using the gm4781 standard,so should i use the dexos 1 or 2?
tnx

 

Just to add some controversy. I put a catch can on mine 5,000km ago. I would get a couple ounces of sludge and water over 1,000km or so. My first oil change as the new owner I used 10W/30. When I checked the can after the first 1,000km I got 1 drop of water. That's it. I would at the very least have expected more condensate.

 

Dexos 1 and Dexos 1 Generation 2 are the new approved oils for most of our cars...Dexos 2 is for Diesel motors...follow the minimum your owner's manual recommends and adjust for what you feel like using...

unless your engine is different from what we have here in the States...Dexos 1/Dexos 1 Gen 2 are both fine...I like Mobil 1 in the proper weight for my cars...

Good luck with your choice

Bill

 

i use the m1 5w30 dexos 1 and change it and oem filter and o ring every 3000-3500km,my engine is very quiet and does not consume almost any oil touch wood.
the dexos 2 is not only for diesel btw.

 

If you truly are changing your oil every 3000-3500km You are doing it WAY too often. Luckily the only thing you will hurt is your wallet as long as you don't weat out the threads from anything you have to unbolt or unscrew.

The original was 3000 miles.

If your changing at 3000km that is roughly 1800 miles and barely over half way under the OLD suggested mileage. And even the most oil consumption vehicles you would be pressed to be more than a quart low. Newer mileage suggestions are 5000 miles between oil changes. I have been told that the oil change frequencies in our cars are too long if you go by the "oil life" measure and have seen suggestions to change oil when that get to 40%. If your using Mobile 1 or other high quality synthetic oil and a good quality oil filter it is not unreasonable to get up to 10,000 miles on one oil change. Especially if you have a high consuming vehicle and are adding another quart every 1500 miles or so.

Rodney

 

For oil duty you need to read the labels. Look at the MOM site link - many oils are rated for gasoline AND light diesel duty. Just because an engine il is rated for diesel duty does, in no way, make it unsuitable for gasoline engine duty.

Oil viscosity and a catch can have no bearing on how much oil/acid/moisture vapor may be trapped instead of simply burned as the PCV systems were designed to do. You drive in Saudi Arabia, your total condensed moisture (from air drawn in as the engine cools) is very low; you drive in sticky Charleston, SC or Seattle on a cool, humid morning (you cut the air with a knife) you get more internal moisture. PCV systems draw off and burn moisture and acid vapor - catch cans trap some of the oil vapor from a high flow - and perhaps improperly baffled - PCV system. Forced induction, when used, also increases PCV carryover.

 

I appreciate your insiteful reply. I am relaying my experience. My PCV system is stock and nothing else has changed. Your understanding of this system is quite complete. Have you any other ideas what might produce this result?
I will keep tabs on my catch cans contents to see if this is an anomalous result.

 

Just send me your $$ and we'll both be happy! Your are wasting your money and your oil. Using 100% synthetic, you should be getting at least 7,500 miles on your oil (provided that you check your oil level and add when necessary). Vram

 

what gasoline engines spec Dexos 2???...perhpas this specification means something else outside of the States...why would you use Dexos 2 motor oil?...are there any benefits to using this?

I just went from an online GM specification between Dexos 1 and Dexos 2 that stated "2" was for Diesel...good luck with whatever oil you choose.

Bill

 

have either of you who mentioned using Dexos 2 come up with any benefits from using Dexos 2 instead of Dexos 1, Dexos 1 Generation 2 or non Dexos oil???

Bill

 

mtrh, Surf through the newer model forums and find threads concerning catch cans - by SC2150, Mishimoto, others - particularly on the 3.6DI engines. Lots and lots of discussion and how-to info over the last 4 years - it's all in here somewhere.

I agree that a 3,000 km oil change schedule is WAY too early. Today's oil is marvelous stuff and, given today's gasolines an engine driven under a mix of city, rural, and highway conditions will easily - easily - go 5,000 to 8,000 miles on an oil and filter change.

My 2002 Northstar gets over 6,500 miles to the quart of 5W-30 synthetic, the car is now pretty much a garage queen, and so the oil/filter gets changed at 5,000+ or once a year, whichever occurs first. What drains out is clear, light amber colored and oil condition lab tests from Blackstone reveal that the old oil has at least another 5,000 miles left as-is. Some of the GM OLMs (Oil Life Monitor) are set to 12,500 miles. The description of the early algorithm-driven monitors is way up ^^^ in the [Northstar] Cadillac Technical Archive in the top black bar. Newer OLMs also use an oil turbidity sensor.

These days are gone forever ..............

 

most travels are like 2miles to work and back,thats why the oil life is short.change oil when its around 40%.

 

I would never go more than 5,000 miles between oil changes. 3500 is the max for me but I'm old school.

I just did an oil change on my CTS4.

I used 5 quarts of the Castrol and 1 quart of Mobil 1 because it was the cheapest single quart synthetic at Crapmart.

I also threw in a magnetic drain plug. I'll post pics if I find any metal shavings.

Advanced Auto is running a sale right now. 5 quarts of Castrol synthetic and a K&N filter for $22.99 after the mail-in rebate.

 

I go over 10,000 miles on mine. Mobil 1, new filter and new O-ring plus I send a sample off to Blackstone for testing. Monitoring your oil via lab testing allows maximizing your oil change interval with facts, thereby making an informed decision instead of an advertising myth.

 

What is the fee for Blackstone? I drive mine so sparingly that I only change the oil once per year.

 

I'll check tomorrow for sure. I get the additional test that tells me how much "life" is left in the oil, which helps determine oil change intervals.

 

They break down many of the metals and chemicals in your oil that may give you insight into what is going on internally. My first engine was in great shape 'til I took my stupid pill and blew it up. Oh, by the way, change your O-ring when you change your filter.

 

Thanks, brother. My last oil change was 06-18-16 @ 42,613 and I'm at 46,372 now. OLM shows 64%

 

You don't need that extra cost test, that's for sure. I'll post up tomorrow.

 

About $30 with postage now ........... You pull a sample from either the drained oil or the dipstick tube and send it in. Tell them what oil you normally use so they have a baseline to work from.

http://www.blackstone-labs.com/

 

is dexos better than "regular"synth oil?

 

No. Dexos is merely a "standard" GM has set up for oil manufacturers. It is nothing special, just a marketing tool as well as an income generator for GM. If you want to do business with GM, then you have to have the Dexos stamp on your oil.

Imagine going to the store to purchase oil. Your car manual says "use only Dexos II oil". What kind of oil are you going to purchase/use? Yes, oil with that Dexos stamp on it.

 

i think the eu cts models use the dexos2

 

also heard that the 4718m oil are better than the dexos is it true?

 

That oil is spec'd by GM for Corvettes.

 

The 2017 Vette owners manual calls for Dexos1 oil except for the dry sump engines where they recommend Mobile 1, the GM4718m is an old spec.
"Selecting the Right Engine Oil Selecting the right engine oil depends on both the proper oil specification and viscosity grade.
See Recommended Fluids and Lubricants 0 316. Specification Ask for and use engine oils that meet the dexos1™ specification.
Engine oils that have been approved by GM as meeting the dexos1 specification are marked with the dexos1 approved logo.
See www.gmdexos.com. GM recommends Mobil 1® engine oils that show the dexos1 approved logo for its dry sump equipped engines."