Conventional 5W-30 No Longer Available?

[Schurkey]

Far as I'm aware, there has been NO "Dexron III" since 2006, except for Dexron IIIH which went until 2011. After that, the word "Dexron" was removed from the label, with just "III (H)"

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But there's conflicting information about the use/non-use of the word "Dexron".

Plenty of companies sell "compatible" products under the "Dex(ron) / Merc(on)" "Dex/Merc" or "D/M" descriptions.

Best I can tell, GM's AutoTrac II is Dexron III with blue dye instead of red dye. But don't take my word for it.

 

[Pinger]

Read that the "additives" in conventional oils that have a wide W spread (10w-40) etc. promote varnish/coke build up UNLIKE oils that have a tighter w (10w-30). Fact or Fiction?

GM quit suggesting 10W-40 decades ago. I could never get a straight answer "why", except that there were vague references to additive package, and "too much" additive was needed to get the wider viscosity range. The GM "Goodwrench" oils back in '83--'84 were not available in 10W-40.

What makes multi-grade possible is viscosity improvers. They are long-chain polymers, part of the additive package and in service get 'chopped up' such that they are no longer long-chain. Gears are particularly bad for this which is why on the likes of big boats/ships which have lots of gear driven take-offs a straight oil is still used. That, and the lesser emphasis on cold start capability.

Viscosity improvers are easiest understood by looking at your own hands. Curl your fingers into a ball. That is how viscosity improvers are when cold. Curled tight they offer least impediment to flow and thus reduce the oil's viscosity. Now extend and stretch your fingers. That is how viscosity improvers are when hot. The long-chain aspect kicks in and they are more obstructive to flow hence the increase in viscosity.
It is easy to see how vulnerable they are to being 'chopped up' and how that impacts on the high temperature viscosity.

 

[HotWheelsBurban]

What makes multi-grade possible is viscosity improvers. They are long-chain polymers, part of the additive package and in service get 'chopped up' such that they are no longer long-chain. Gears are particularly bad for this which is why on the likes of big boats/ships which have lots of gear driven take-offs a straight oil is still used. That, and the lesser emphasis on cold start capability.

Viscosity improvers are easiest understood by looking at your own hands. Curl your fingers into a ball. That is how viscosity improvers are when cold. Curled tight they offer least impediment to flow and thus reduce the oil's viscosity. Now extend and stretch your fingers. That is how viscosity improvers are when hot. The long-chain aspect kicks in and they are more obstructive to flow hence the increase in viscosity.
It is easy to see how vulnerable they are to being 'chopped up' and how that impacts on the high temperature viscosity.

Very well said, that explains it nicely!

 

[1990C1500]

As per the title...

I was shopping around today for a 5qt jug of conventional 5W-30 to replace the empty one from my garage stash, and I couldn't find any from the usual brands! Walmart and O'Reillys both only had synthetic blends or full synthetic. That prompted me to do a little research and it looks like the major manufacturers are no longer producing conventional oils, at least in certain viscosities. Valvoline and Pennzoil's websites both seem to back this up. I could find some old stock on Amazon and Summit, but they were few and far between. I found some threads on other forums that seem to echo what I discovered today as well.

Am I going crazy or is this really a thing? Is conventional oil going away entirely?

Where are you located? I'm in broken arrow Oklahoma and the oreillys I work at has plenty and sells a lot of it. I work in the back as delivery driver and training as an ISS selling parts to the shops. I put away most of the stock, no one touches the batteries or oil but me so I see what we go through.

 

[df2x4]

Where are you located? I'm in broken arrow Oklahoma and the oreillys I work at has plenty and sells a lot of it.

Central Missouri.

Odd that your location has it but mine and the one @L31MaxExpress was at didn't...

 

[1990C1500]

Central Missouri.

Odd that your location has it but mine and the one @L31MaxExpress was at didn't...

We stock transfer parts from Springfield every morning. I'm surprised they didn't offer to get you some. Our oil rack out front is full and we have a bunch in the back.

 

[df2x4]

We stock transfer parts from Springfield every morning. I'm surprised they didn't offer to get you some. Our oil rack out front is full and we have a bunch in the back.

Just out of curiosity to make sure we're on the same page, do you all have any standard Pennzoil 5W-30 in the yellow 5qt jugs? If so go look at the bottom right corner of the label. Does it say "Synthetic Blend" right above the words "Motor Oil"? EDIT - Bottom left, my bad.

My issue isn't finding the standard offerings from the major brands, it's that they all seem to be marketed as "synthetic blends" now.

 

[1990C1500]

Just out of curiosity to make sure we're on the same page, do you all have any standard Pennzoil 5W-30 in the yellow 5qt jugs? If so go look at the bottom right corner of the label. Does it say "Synthetic Blend" right above the words "Motor Oil"? EDIT - Bottom left, my bad.

My issue isn't finding the standard offerings from the major brands, it's that they all seem to be "synthetic blends" now.

Orileys brand containers and some others.

 

[df2x4]

Orileys brand containers not the other brands.

Ah OK, thanks for clarifying. I didn't even look at the O'Reillys brand stuff, I usually stay away from the cheaper store brand oils. Wonder why they haven't changed anything on the packaging while it seems like most of the big names have?

 

[1990C1500]

Ah OK, thanks for clarifying. I didn't even look at the O'Reillys brand stuff, I usually stay away from the cheaper store brand oils. Wonder why they haven't changed anything on the packaging while it seems like most of the big names have?

I was wrong and edited my response. We do have other brands. Even text messaged a coworker to double check.