5W30 oil

[Grumpy Bear]

7 hours ago, asilverblazer said:

I KNOW I can get 250K miles using GM's recommendation, with oil consumption.

 

Pepper is at 185,000 and uses no oil and the AFM is working perfectly ignoring the OEM recommendations for OCI and oil spec.  

 

Yes, yes.... you'd be right....Question still hanging is; for how long.  I can't read the future, but I can read a rocker box and a compression gauge and at somewhere around 165K it looked new: 

 

Not a brag...A result.

 

 

 

 

 

[Grumpy Bear]

 

[Service1956]

After watching the video, guy mentions oil life monitor. Waiting near 0% and having 7-10000 miles. Sometimes up to 12000. And then wonders why it uses so much oil.

[customboss]

1 hour ago, Service1956 said:

After watching the video, guy mentions oil life monitor. Waiting near 0% and having 7-10000 miles. Sometimes up to 12000. And then wonders why it uses so much oil.

Audi allows high drain intervals. Their engines are known to coke the piston top down from fuel. 
Engine oil had nothing to do with this failure. 
 

 

[Snow White]

big fan of lake speed jr.  0-20 oil is a joke, it's epa oil, thinnest possible oil to get most mpgs for their fleet mpg and reduce fines.  do we care about that.....?  NOPE.

 

i used napa 5w-30 because the viscosity holds better than the barely 40w supercar mobil 1 and has more molyb in it according to tests.  i'm at 7500.  took out the oem at 1000, put in 0w-20 napa at 1000-5000, now running 5w-30 and will probably stick with it. instantly went quiet with the 5w-30 for what it's worth.  i might try a 5w-40 if i can find a dexos version of it.

[KARNUT]

My Grandaughter stopped by to visit with her 09 Mazda 3 my wife found. We bought it for 500$ with close to 150K miles on it. That was 2021. Her Chrysler 300 was approaching 300K miles on it. We were worried this seemed better. To date she needed minor AC work. At first it had a transmission leak that resolved on its own. She uses the same Valvoline quick lube I use. It’s never had transmission service. She’s put over 100K miles on it. I get more convinced that more than oil change intervals, even transmission service. It’s what you drive that makes more difference. I remember her calling me saying her steering was acting up on the Chrysler. I told her get a turkey paster and pull out the fluid it and put new in, that fix it. My niece has the twin to my Ridgeline only it a SUV. Once I started messing with Hondas I became familiar with their maintenance. I asked my brother if the timing belt was replaced on his daughter’s SUV. He got it done right away at 140. At 200K it’s never had transmission service. Recently spark plugs. My list is very small on vehicles I’ll buy. I rather have tough vehicles that handle abuse. And treat them to frequent service. Than have to do it for them to survive. 

Edited July 28, 2025 by KARNUT

[Black02Silverado]

16 hours ago, Snow White said:

big fan of lake speed jr.  0-20 oil is a joke, it's epa oil, thinnest possible oil to get most mpgs for their fleet mpg and reduce fines.  do we care about that.....?  NOPE.

 

i used napa 5w-30 because the viscosity holds better than the barely 40w supercar mobil 1 and has more molyb in it according to tests.  i'm at 7500.  took out the oem at 1000, put in 0w-20 napa at 1000-5000, now running 5w-30 and will probably stick with it. instantly went quiet with the 5w-30 for what it's worth.  i might try a 5w-40 if i can find a dexos version of it.

AMSOIL's European 5w-40 is dexos 2, I know it's a diesel rating but in the dexos line and it's listed for both gasoline and diesel applications.

 

https://www.amsoil.com/p/amsoil-5w-40-ms-100-synthetic-european-motor-oil-afl/?zo=521390

[Black02Silverado]

On 4/11/2025 at 9:34 PM, Grumpy Bear said:

 

But what about an oil listed for both gas and diesel?  Such as this.  

 

https://www.amsoil.com/p/amsoil-5w-40-ms-100-synthetic-european-motor-oil-afl/?zo=521390

[Grumpy Bear]

5 hours ago, Black02Silverado said:

But what about an oil listed for both gas and diesel?  Such as this.  

 

https://www.amsoil.com/p/amsoil-5w-40-ms-100-synthetic-european-motor-oil-afl/?zo=521390

 

I rewatched the video. Seems pretty straight forward. 

 

This oil you referenced is rated for allot of uses and among them the API category CF which is diesel and also obsolete and has been since 2009. So kind of a non question question. Having a rating is less important than have the right one, correct? 

 

BTW, @Snow White,  Dexos 2 isn't a diesel rating. Dexos D is. Dexos 2 is a 3.5 HTHS minimum spec. Like AECA C3

 

As far as why there are oils with duel ratings.... yea, I don't read tea leaves. I don't like marketers. I like results and lab data. Don't think I'll be much use on this question. 

 

[Black02Silverado]

32 minutes ago, Grumpy Bear said:

 

I rewatched the video. Seems pretty straight forward. 

 

This oil you referenced is rated for allot of uses and among them the API category CF which is diesel and also obsolete and has been since 2009. So kind of a non question question. Having a rating is less important than have the right one, correct? 

 

BTW, @Snow White,  Dexos 2 isn't a diesel rating. Dexos D is. Dexos 2 is a 3.5 HTHS minimum spec. Like AECA C3

 

As far as why there are oils with duel ratings.... yea, I don't read tea leaves. I don't like marketers. I like results and lab data. Don't think I'll be much use on this question. 

 

dexos 2 was what GM stated to use in their diesel engines like when I had me diesel Cruze, but then changed the specification to dexos D.  dexos 2 is being phased out by 2026.

 

You might of been thinking of dexos gen2, which there is now a gen3.

[Grumpy Bear]

4 minutes ago, Black02Silverado said:

dexos 2 was what GM stated to use in their diesel engines like when I had me diesel Cruze, but then changed the specification to dexos D.  dexos 2 is being phased out by 2026.

 

You might of been thinking of dexos gen2, which there is now a gen3.

 

Likely correct

 

Everything has an expiration date. Mine is sooner than later. 

 

I posted the video more for what one can learn from the implications then what he actually said. There was allot of meat on those bones. 

[Snow White]

emailed lake he said not to change viscosity without UOA.  was looking at valvoline VR1 and valvoline advanced.  only the 20w-50 has the correct NOOACK value.  VR1 is not good for catalytic converters I read?  outside of boutique oil, the napa version of valvoline seems really good.  i have 2500 miles to go before my 5k change.  it'll take 2-3 drains to get all the 0w-20 napa out of there.

 

getting 19mpg with a range installed, 3.5" ready lift, 33x12.5R22 nittos... hard to argue with that.  not that i care much about the mpgs but it's notable for others.

[Grumpy Bear]

@Black02Silverado

 

https://360.lubrizol.com/Specifications/GM/GM-dexos2

 

I think the difference is going to be in service on this one. Diesel oil? Yes and No...light duty automotive diesel, not OTR and yes, it has a minimum 3.5 HTHS as I thought. The list of approved oils is silly short in both weights. Here's one of them

 

https://www.castrol.com/content/dam/castrol/master-site/en/global-ia/home/africa/documents/products/edge-5w30-c3-pds.pdf

 

This is exactly what it says on the data sheet. 

 

Application:

 

Castrol EDGE 5W-30 C3 is suitable for use in automotive gasoline and diesel vehicles where the manufacturer recommends: ACEA C3, API SN/CF 5W-30 Lubricant Castrol EDGE 5W-30 C3 is approved for use in vehicles from leading manufacturers, please refer to the product performance section and your owners handbook. *GM dexos2TM: supersedes GM-LL-B-025 and GM-LL-A-025 : GB2E0209082

 

There is that obsolete CF classification again. Yet Dexos 2 approved for diesel nonetheless. 

 

So yea, it has a diesel certification and No it isn't useful as a universal diesel oil. Don't put it in you Cat or CUMMINS. 

 

Basically this is a Euro Spec ACEA C3 oil that won't kill a Cruze. 

[Snow White]

just drained my Napa 5w-30 and put on a new WIX.  Waiting for the lab kit, forgot to order it before i did the drain but the drain is more important than letting the oil sit in a cleaned out vitamin water bottle with a cap for 2 days LOL.  (i used soap and water and rinsed it excessively).

 

i'll post the results as usual.

this will be a 5K OCI.

[PunchT37]

Just sent my 3000 mi. 5w30 sample out yesterday. 6700 miles on truck. High copper on 1`st 2 samples. 1`st one done at 500 miles. It does have the extra coolers as it has the NHT package. So, maybe the cooler is the cause of the high copper. We`ll see. 5.3L