Stellantis 6.7L Cummins TSB: Only use 10W30 on 2019MY+, 15W40 can cause damage

[tnt_motorsports]

The 2019+ 6.7L Cummins is the first to have hydraulic lifters in the Rams. I have heard through the Cummins form that this is the theory behind the specification for 5w40 and 10w30.

Positive no more valve lash adjustment, negative having to run more expensive 5w40 oil. I think I’d rather adjust valves every 150,000 miles.

Just my $0.02

 

[kschachn]

The 2019+ 6.7L Cummins is the first to have hydraulic lifters in the Rams. I have heard through the Cummins form that this is the theory behind the specification for 5w40 and 10w30.

Positive no more valve lash adjustment, negative having to run more expensive 5w40 oil. I think I’d rather adjust valves every 150,000 miles.

I don’t understand. How would that affect the adjustment interval?

 

[The Critic]

I don’t understand. How would that affect the adjustment interval?

Having Hydraulic lash adjusters means no more manual valve adjustments.

 

[JHZR2]

I think that would be it, yes. Low oil flow in the valve lash adjuster, so the mineral stuff is likely to largely stay there after oil changes and degrade further into the next oci... once the thickening starts it will be even harder to get out.

That’s an interesting angle. But the flow would have to be so low that it’s nearly nonexistent. At that point, in a lifter, no access to oxygen, no real flow, other than shearing what’s the mechanism of “wear out”?

 

[kschachn]

Having Hydraulic lash adjusters means no more manual valve adjustments.

Yeah sorry I missed that part. But still I can't really get the connection between any of this and grade. It has to be an assumption that cheap(er) 15W-40 is being used that has inferior base stocks and VII. As far as 10W-30 goes it has to be a similar assumption.

 

[Jetronic]

That’s an interesting angle. But the flow would have to be so low that it’s nearly nonexistent. At that point, in a lifter, no access to oxygen, no real flow, other than shearing what’s the mechanism of “wear out”?

Heat I suppose

 

[wpod]

Interesting, I haven't heard a peep about this at all. But, as far as I know, were aren't using any hydraulic valve lash adjusters on the commercial B6.7's either. So that's probably why. The Ram versions do have quite a few differences vs our commercial engines. Our commercial engine owner's manuals for 2019 and older still state "While the preferred viscosity grade is 15W-40, lower viscosity multigrade oils can be used in colder climates." Newer model years states "Use of 10W-30 is recommended for normal engine operation and provides the best wear protection. 15W-40 is compatible for improved engine durability at extremely high ambient temperatures."

The nice thing about BITOG is the industry pros [ in many fields] we have onboard.

 

[53' Stude]

View attachment 107650

https://static.nhtsa.gov/odi/tsbs/2020/MC-10178698-9999.pdf

Was advised by a few reputable dealer techs than 15W40 was causing the pushrod and rocker arm issues, and this is one of the reasons why Stellantis came out with this TSB.

Any thoughts on this? Surprised to see a 15W-xx oil cause issues compared to a 5W-xx or 10W-xx in >0F conditions.

I smell a rat

 

[SteveG4]

I smell a rat

Yep. Something's fishy here.

 

[Gokhan]

View attachment 107650

https://static.nhtsa.gov/odi/tsbs/2020/MC-10178698-9999.pdf

Was advised by a few reputable dealer techs than 15W40 was causing the pushrod and rocker arm issues, and this is one of the reasons why Stellantis came out with this TSB.

Any thoughts on this? Surprised to see a 15W-xx oil cause issues compared to a 5W-xx or 10W-xx in >0F conditions.

This has nothing to with the SAE viscosity grade. It has all to do with the base-oil quality. API CK-4 15W-40 base oils are typically a Group II conventional, with CK-4 10W-30 base oils being a Group II & Group III synthetic blend and CK-4 5W-40 base oils being a Group III synthetic.

If you use a full-synthetic CK-4 15W-40 such as Mobil Delvac Extreme 15W-40, it will leave less deposits than a synthetic-blend CK-4 10W-30.

Mobil Delvac Extreme 15W-40 at Walmart

It is also true that thinner base oils have a lower aniline point, therefore higher solvency and better cleaning ability. Since 15W-40 base oils are very thick, they lose points in this aspect. (A 15W-40 oil accomplishes the SAE 40 viscosity without the help of a lot of VII thanks to a thick base oil.) However, a thicker base oil also results in substantially less wear, scoring very high in that area.

 

[mobilnissan1991]

Been using 15W40 in my buddies 2019 for 67k miles and 3 years with no issues, because he has a huge supply of it and no concrete reason in the manual to not use it. Few months ago when they came out with this TSB I finally convinced him to run 5W40 T6

 

[dnewton3]

FACT - oil viscoity is a rating of it's resistance to flow, rated at some temp. It speaks NOTHING to a propensity, or lack thereof, to forming deposits.

FACT - many common lubes in the market place use different base stocks and add packs to achieve their intended goal

Let's look at some common market options here ...
Products such as Rotella T6 5w-40 are generally a grp III oil with a huge slug of VIIs to achive the vis spread.
Products such as Amsoil DEO 5w-40 are generally PAO, yet achieve the same vis spread with little/no traditional VIIs.
Products such as Amsoil AME 15w-40 are generally PAO with even less in the way of a vis spread.
Products such as Rotella T4 10w-30 are a group II+/grp III with enough VII to achieve a grade range of "20" (30 hot - 10 cold).
Produts such as Delvac 1300 15w-40 are a group II+ with enough VII to achieve a grade range of "25" (40 hot - 15 cold).

So why does Stellantis say all 5w-40 lubes are OK year round, when there are several products that are group III with a large dose of VIIs?
Yet dino products with less VIIs are not ok? I would presume that Shell's Rotella T4 15w-40 has less VIIs than does their T6 5w-40, does it not?
So a 40 grade is OK ("5w-40"), but a 40 grade is not OK ("15w-40").
Yet a 40 grade could be a "dino" 15w-40, but what about a syn 15w-40 Amsoil AME?
So a PAO 15w-40 is not OK, but it's somehow OK to use a grp III 40 grade???

I am not a tribologist, nor do I make a living developing add-packs. I would defer to many of our credible experts in the field to weigh in here. I may be totally wrong, and I am willing to admit I certainly could be wrong, so please don't take my word as gospel here. But the way I see it, this is just total bovine scat. This statement make HUGE presumptions about grade, with absolutely no understanding of how base stocks and VIIs play into those viscosities. It completely ignores the nuances of how each indivual product is designed, marketed, and packaged for an intended application. It seems that there's probably a detailed explanation that got lost in corporate translation. Because I cannot fathom how they can reconncile this statement with facts about lubes.


Are we confident this is a verified Stellantis release and not hokum?

.

 

[DuckRyder]

Are we confident this is a verified Stellantis release and not hokum?

.

Based on the NHTSA ODI (office of defects investigation) link in the original post, yes.

 

[ceecbtg]

Good Shell publicity...

 

[OVERKILL]

Produts such as Delvac 1300 15w-40 are a group II+ with enough VII to achieve a grade range of "25" (40 hot - 15 cold).

According to Mobil, you can do a CI-4 15w-40 with Group I:

AP/E CORE is Mobil's slate of Group I products:

So, that may weigh-in here.

 

[loneryder]

It must be from breakdown of the VII.

Slower flow?
Just saw that flow has been covered.

 

[levi]

This thread is overall an interesting reversal in recommended motor oil wisdom.

Typically it's, 'stay with the manufacturers recommended viscosity'.

Now it's, 'I'm not so sure'.

 

[53' Stude]

This thread is overall an interesting reversal in recommended motor oil wisdom.

Typically it's, 'stay with the manufacturers recommended viscosity'.

Now it's, 'I'm not so sure'.

I take out of this thread “is 15w40 is bad for any Diesel engine; just ask us!” Which is a load of

My farmer friend has a 19’ Ram 2500 diesel truck, runs 15w40 year round with ZERO issues that’s 0.

 

[levi]

I take out of this thread “is 15w40 is bad for any Diesel engine; just ask us!” Which is a load of

My farmer friend has a 19’ Ram 2500 diesel truck, runs 15w40 year round with ZERO issues that’s 0.

For some reason, ELO's Confusion keeps playing in the back of my mind.

Gotta love BITOG. And I guess I do.

 

[JHZR2]

I take out of this thread “is 15w40 is bad for any Diesel engine; just ask us!” Which is a load of BS

My farmer friend has a 19’ Ram 2500 diesel truck, runs 15w40 year round with ZERO issues that’s 0.

How many miles? How hard of use?

One test is no test.

Are you saying that Dodge/Cummins is lying about what they’ve encountered?