Rotella T Synthetic, 5w40 5070 mi, 2003 Deville

[ronrackley]

The last OCI, in January, was with 20% (1.5 quart) Marvel Mystery Oil (MMO) in Rotella Conventional 15w40. That was a clean-up run on the newly purchased used 2003 Deville. I had replaced it for this last OCI with what I normally run, straight Rotella T Synthetic 5w40 (RTS). I had an analysis run after the first OCI just out of curiosity about the MMO.

After seeing the exceptional wear metal numbers with 20% MMO, I decided to run another analysis with this straight RTS to get something like a baseline. The numbers looked almost as good. I'm trying 20% MMO in RTS this next OCI and I'll run another analysis at the next change. I know I may be raking around in the "noise level" of the measurement process comparing numbers this low, but it interesting to see that the MMO not only did not hurt, but if anything it helped, and that this Northstar engine seems to love the Shell Rotella products.

The dipstick level had dropped about 1/2 quart the first OCI with no make-up oil and it dropped about the same - maybe closer to 1/3 quart - this time. I saw no evidence of significant leaking or "burn-off" with the MMO in this engine which was interesting, because I have seen MMO when run to quiet lifters cause excessive oil loss in older engines.

 

[ZZman]

I am confused.

Where is all the Calcium?

Did they switch Magnesium for some Calcium?

 

[willix]

5w40 seems to a heavy weight for a N* engine. Why 40? You would have more positive flow with the recommended 30W's and better MPG in the longrun.

 

[ARCOgraphite]

This is the wrong oil for this car, you DO NOT want majority Mg dispersant/detergents in a gasoline engine. It is also WAY to high viscosity. Try the RT5 10w-30 or just use a high mileage oil like pennzoil or Maxlife for the extra FL cushion.

 

[ronrackley]

Originally Posted By: ZZman
I am confused.

Where is all the Calcium?

Did they switch Magnesium for some Calcium?


I noticed that too.

Also this Rotella T Synthetic 5w40 had very significant Moly that the Rotella conventional 15w40 oil of the previous OCI did not have. I didn't realize that the two types of Rotella would have such significant differences in their additive packages.

Both oils were purchased last year. The 15w40 was their newer "triple protection" in the rounded handle white jugs. The 5w40 was the new type (CJ) in the rounded handle blue jugs.

Interesting!


The Rotella

 

[ronrackley]

Originally Posted By: willix
5w40 seems to a heavy weight for a N* engine. Why 40? You would have more positive flow with the recommended 30W's and better MPG in the longrun.


Well, the 40 is because the very good HDEOs I can find on the shelf at good prices around here are either 5w40 or 15w40, depending on whether they are conventional or synthetic, and I like to run HDEO that is also rated on the bottle for Gasoline engines in my gasoline engines.

I am not able to tell any difference in gasoline mileage. About half my mileage is on our flat Florida interstate highways with cruise control set to 75 miles an hour most of the time (don't tell on me) and I see no significant difference when I run PP 10w30, which I have tried recently and believe is a perfectly good oil, at gas pump or on the on-board MPG monitor. I know that careful testing might reveal a tenth or two of a mile per gallon difference, but I see larger differences than that depending on which way the wind is blowing.

 

[ronrackley]

Originally Posted By: ARCOgraphite
... you DO NOT want majority Mg dispersant/detergents in a gasoline engine...


I have not heard this, but I am interested in learning more about it.

 

[Nick R]

This oil is fine for your car. People recommend HDEO such as rotella for cars all the time, (namely Jeeps with the 2.5 or 4.0L Inline AMC engines). Good looking UOA.

 

[Rob_Roy]

Originally Posted By: ronrackley
Originally Posted By: ARCOgraphite
... you DO NOT want majority Mg dispersant/detergents in a gasoline engine...


I have not heard this, but I am interested in learning more about it.


Me too, especially with all the CJ-4 oils that also meet API SL. The new Rotella 5w40 also has API SM listed.

As for this oil being "way too thick", I don't think the heavier viscosity is required, but I also don't think it will hurt anything. The wear metals are very low, oil consumption is low (for a Northstar), and the fuel economy hasn't changed.

Stay the course...

 

[calvin1]

You'll never find a 10w30 HDEO on the shelf in Florida. It's seasonal even here in Chicago. You'd have to special order it but I don't think that really makes sense in your case.

 

[Boss302fan]

The Northstar engines love Maxlife blend 10W30. My son has used it in his 99 Olds Aurora for around 2 years and his engine is really running great. Northstar's are known to use oil and his oil consumption has dropped to only around 1 quart every 3K-4K miles.

 

[Hokiefyd]

Originally Posted By: calvin1
You'll never find a 10w30 HDEO on the shelf in Florida. It's seasonal even here in Chicago. You'd have to special order it but I don't think that really makes sense in your case.


That used to be the same here, too. But Walmart is stocking the new Rotella T5 or whatever it is in 10W-30. I think my Dakota will get that next.

 

[Jax_RX8]

Everyone is ignoring the obvious here - that the MMO/Rotella OCI actually had slightly better wear numbers than the pure RTS OCI.

This is one of many UOA's on here now that continue to show that the addition of MMO to the oil not only cleans very well (as many on here acknowledge), but can actually improves wear numbers for many - and at the very least not worsen them while keeping the engine much cleaner.

MMO is the real deal. We always ask for real data - here is a very good head-to-head example as the RTS numbers should have been better, not worse (albeit slightly), based on it being the premium version of Rotella.

 

[ronrackley]

Originally Posted By: Rob_Roy
...oil consumption is low (for a Northstar)...


I know about oil consumption and Northstars, as we had 2000 and 2001 Devilles before we got the 2003 and 2005 ones that we now drive [we like them a lot] and they were always thirsty for oil. I got the 2000 with about 20,000 miles on it in 2001 and started out having to add a quart about halfway through every 5000 mile OCI. By about 160,000 miles when I sold it the consumption was up to about a quart every 1,000 - 1,200 miles depending on the oil. I tried Maxlife and Pennzoil HM but got the best usage - but still not great - with Rotella 15w40. My wife's 2001 Deville could go through a quart in 600 - 800 miles by 140,000 miles. There were minor drops on the driveway from both cars but nothing major. Both ran great and it was a mystery to me where all that oil was going. By contrast, my 2003 uses about 1/2 quart in 5000 miles and it is hard to tell if my wife's uses any at all because the drop on the dipstick is so small. I think they addressed the oil problem in a redesign before 2003.

 

[JoeFromPA]

Looks exceptionally clean; the MMO doesn't appear to be hurting or helping. I wouldn't run it, period.

As for the oil viscosity: excellent choice. It's not way too thick, despite what others might say. It's just right

 

[Hokiefyd]

Northstars love 40WT oil. My old '97 got REAL smooth on 15W-40 Rotella.

 

[BigJohn]

Originally Posted By: Jason Adcock
Originally Posted By: calvin1
You'll never find a 10w30 HDEO on the shelf in Florida. It's seasonal even here in Chicago. You'd have to special order it but I don't think that really makes sense in your case.


That used to be the same here, too. But Walmart is stocking the new Rotella T5 or whatever it is in 10W-30. I think my Dakota will get that next.


Yep, both my Walmarts have loads of T5 on the shelves.

 

[panthermike]

Originally Posted By: Jax_RX8
Everyone is ignoring the obvious here - that the MMO/Rotella OCI actually had slightly better wear numbers than the pure RTS OCI.

This is one of many UOA's on here now that continue to show that the addition of MMO to the oil not only cleans very well (as many on here acknowledge), but can actually improves wear numbers for many - and at the very least not worsen them while keeping the engine much cleaner.

MMO is the real deal. We always ask for real data - here is a very good head-to-head example as the RTS numbers should have been better, not worse (albeit slightly), based on it being the premium version of Rotella.


Good point, I'm impressed with the MMO/Rotella run, looks good. HDEO's do well in this engine.

 

[willix]

I think it was 2003 the N* upgraded the direct cam design and added a rollerized valve buckets and the need for better shear is greatly reduced. I believe the 20W's will do well in the later model N*'s. No matter how hard you try a Deville N* just doesn't have a very hard life.

 

[ThirdeYe]

Originally Posted By: ARCOgraphite
This is the wrong oil for this car, you DO NOT want majority Mg dispersant/detergents in a gasoline engine. It is also WAY to high viscosity. Try the RT5 10w-30 or just use a high mileage oil like pennzoil or Maxlife for the extra FL cushion.


Yeah, it definitely looks like it's about to cause this engine to grenade itself based on these wear numbers.