224k UOA for 2006 6.0L PowerStroke - Mobil 1 TDT 5W40

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224k UOA for 2006 6.0L PowerStroke - 4000 miles on Mobil 1 TDT 5W40 oil. UOA attached.

I wanted to catch the sample right as the Mobil 1 TDT 5W40 oil sheared to the very top of the 30 wt. range. It happened at apprx. 4000 miles.

Link to previous post on Mobil Delvac 1 5W40:
 

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Good observation! I used the Delvac ESP 5W40 the last oil change. An oil changes only replaces a little over 80% of the oil that is in the system, so a fair amount of residual oil is going to be there.
 
I read the other thread you pointed to, interesting data.
Looks like same or very similar add pack between Delvac and TDT. Maybe difference in base oil? But both seemed to have sheared the same with your use.

I don't like seing tin in a UOA, even only 1ppm :unsure:
 
Would this oil be ok to run in an 05 Toyota Corolla? I have some of this oil on hand and an oil change coming up in this car. Thanks.
 
I don't think your Toyota would care. I ran the TDT in my Mazda...that calls for 5W20 in Canada and 5W40/10W40 in Europe 😄
Edit: it's a somewhat high Phosphorus formula, so if your car is burning a lot of oil, then maybe not a good idea.
 
It doesn’t really burn any meaningful amount. I can always use 2 quarts of this and 2 quarts of Mobil 1 0w20 to get a 30 weight and use up the oil I have.
 
LOL!

Rotella T5 10W30 starts out at a 12 cSt and ends up at a 10.6 cSt after 5.5k miles and we have certainly seen numerous threads on how good 10W30 works in these engines. The HEUI systems are just that way.

My previous (and numerous) oil analyses have shown the Mobil TDT 5W40 dropping to 11.7 to 11.9 after 7500 miles. I'll be just fine.
 
Yeah, it sheared. That happens in Ford 6.0's with the HEUI injection system. The High Pressure Oil Pump chews the hell out of 5w40 oils. Try a 15w40 or 10w30. You're in Texas, so the 15w40 would probably be more appropriate if it's hot.
 
As I have posted, my viscosity is still above what a virgin 10W30 will even start out at, so a 10W30 is of limited value to me, especially at 5000 mile OCI .... assuming all you look at is viscosity. Yes the 10W30 does shear more slowly. Even so, since the 10W30 does shear also (lots of data on this since there are quite a few UOA reports of various 10W30's on various forums), the shearing of the Mobil synthetic 5W40 oils will not drop as low as a 10W30 will (at equivalent miles driven) until over 7500 miles. I have quite a bit of data on the Mobil Synthetic 5W40 oils at 7500 mile OCI's. At this point, my OCI limit is 7500 miles. My injectors are ALL original at 224k miles and I expect to get 250k minimum out of them.

A 15W40 will no doubt hold the viscosity a little better, but my UOA does not indicate any issues with what I am using. Also, a 15W40 will be more prone to experience injector stiction in the 6.0L.
 
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As I have posted, my viscosity is still above what a virgin 10W30 will even start out at, so a 10W30 is of limited value to me, especially at 5000 mile OCI .... assuming all you look at is viscosity. Yes the 10W30 does shear more slowly. Even so, since the 10W30 does shear also (lots of data on this since there are quite a few UOA reports of various 10W30's on various forums), the shearing of the Mobil synthetic 5W40 oils will not drop as low as a 10W30 will (at equivalent miles driven) until over 7500 miles. I have quite a bit of data on the Mobil Synthetic 5W40 oils at 7500 mile OCI's. At this point, my OCI limit is 7500 miles. My injectors are ALL original at 224k miles and I expect to get 250k minimum out of them.

A 15W40 will no doubt hold the viscosity a little better, but my UOA does not indicate any issues with what I am using. Also, a 15W40 will be more prone to experience injector stiction in the 6.0L.
Would a synthetic 15w40 resist stiction better than a conventional? Maybe Rotella T6 in 15w40 grade would be the ticket. Have you experienced stiction in your truck?
 
I would "guess" that a synthetic 15W40 would do better with stiction, but if the temperatures drop below freezing it may result in some stiction issues. Navistar and Ford have had Pure Power add a relief cut on the spool valve coil face that may address this issue with the 15W40.

I have never had a case of stiction with my truck, but many I have helped troubleshoot have had it. I have seen a 2 mpg drop in fuel economy and I am sure that the injectors are showing their age.
 
the 6.0 has been out long enough, along with the Cat engines with the same injection system that certain additive packages have shown to promote stiction, while others have very little reported stiction.

The additive package, in my opinion, has more to do with the stiction issue than oil viscosity, synthetic or non synthetic.
 
The Mobil Delvac 1 5W40 holds its viscosity better than most 5W40 oils I have tried - with one exception.....Schaeffer 9000. The Mobil 1 TDT doesn't do too badly, but it seems to shear just a little more quickly than the Delvac 1. I have tried Rotella T6 and Valvoline PBE and they shear a little more quickly. Also, I saw an iron increase with the Valvoline PBE, but it may have been coincidental. I will say that with the Mobil Delvac 1, the iron returned to normal, but when I would switch to the Mobil 1 TDT, it seemed to level out at an intermediate level (not bad, but not totally back to normal). Far from a statistically valid evaluation, but just something observed.
 
the 6.0 has been out long enough, along with the Cat engines with the same injection system that certain additive packages have shown to promote stiction, while others have very little reported stiction.

The additive package, in my opinion, has more to do with the stiction issue than oil viscosity, synthetic or non synthetic.

I can see that, given the proper ambient temperature range for the oil (ie not using 15W40 when ambient temps were below 20 degrees)
 
UOA at 7422 miles on the Mobil 1 TDT 5W40. Note the viscosity still at 12.23, down from 12.34 - it essentially didn't shear from 4000 miles to 7422 miles. Iron is average around 4.5 ppm per 1000 miles (I think that is pretty good for my engine and for 6.0's in general).
 

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