PU Euro 5w-40 viscosity loss/shear - non fuel

[OVERKILL]

When digging back through some older posts looking for some UOA's for a recent thread I found a number of Pennzoil Ultra Euro 5w-40 UOA's that showed a tremendous amount of viscosity loss. Now, one of them had significant fuel ingress as observed via a large reduction in flash point but another, which ended at the same viscosity, did not.

http://www.bobistheoilguy.com/forums/ubb...VW_#Post3664472

and

http://www.bobistheoilguy.com/forums/ubb..._Eu#Post3632653


Now, I find this somewhat amusing as of course the 5w-40 grades are oft touted as being more stable than the 0w-40 lubricants, yet in this case we have two examples that clearly show this not to be the case. We have what must be hundreds of M1 0w-40 UOA's that don't have this type of viscosity loss, even with significant fuel dilution.

Now, there were some UOA's where viscosity loss was not present (and one from Astro14 where the viscosity actually increased, which I believe indicates oxidation and of course Quattro Pete's UOA's showed very little viscosity loss) but there are others that still ended up like this:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1176065

10.53cSt

Or this one:
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/2253386/1

Where the 5w-40 dropped to 12.1cSt while M1 0w-40 in the same engine remained close to virgin at 13.2cSt

Now of course viscosity loss itself doesn't indicate an issue or that the product did not provide adequate protection and that's not the purpose of this thread, it is more to discuss causes of viscosity loss above and beyond fuel contamination as sometimes even the same model of engine will have very different viscosity loss than another fitted to a different vehicle.

 

[Quattro Pete]

Originally Posted By: OVERKILL
and

http://www.bobistheoilguy.com/forums/ubb..._Eu#Post3632653

This one is odd, I agree.

One strange thing is that there is moly in this UOA. PU 5w-40 does not contain moly, which might indicate he's had some leftover other oil in there or topped of with something different, and who knows what viscosity it was.


Quote:

but there are others that still ended up like this:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1176065

10.53cSt

That's not a Pennzoil Euro UOA.

Quote:

Or this one:
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/2253386/1

Where the 5w-40 dropped to 12.1cSt

He noted that he topped off with a quart of 5w-30 in this one.

 

[OVERKILL]

Originally Posted By: Quattro Pete
Originally Posted By: OVERKILL
and

http://www.bobistheoilguy.com/forums/ubb..._Eu#Post3632653

This one is odd, I agree.

Quote:

but there are others that still ended up like this:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1176065

10.53cSt

That's not a Pennzoil Euro UOA.

Quote:

Or this one:
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/2253386/1

Where the 5w-40 dropped to 12.1cSt

He noted that he topped off with a quart of 5w-30 in this one.



DOH!!! (on the 2nd), but I guess on the bright side that's another 5w-40 that has departed significantly from its virgin viscosity, which should have been 13.6cSt.

Regarding the third, yes, I saw the quart of 5w-30, but I don't think that accounts entirely for the viscosity loss as it should be around 12.8 if we factor that in (assuming that the Ultra 5w-30 is the 10.3cSt product) and we are still well below that

 

[Phishin]

The guy running PPE comes running to the rescue!!

 

[Quattro Pete]

Originally Posted By: Phishin
The guy running PPE comes running to the rescue!!

Have I stated something inaccurate? Let's discuss.

 

[OVERKILL]

Originally Posted By: Quattro Pete
Originally Posted By: OVERKILL
and

http://www.bobistheoilguy.com/forums/ubb..._Eu#Post3632653

This one is odd, I agree.

One strange thing is that there is moly in this UOA. PU 5w-40 does not contain moly, which might indicate he's had some leftover other oil in there or topped of with something different, and who knows what viscosity it was.


Right, we can assume the moly may be from the previous fill, but the viscosity loss sure wouldn't be as the car has a 7 quart sump and even if it was 0w-20 (which we can probably be pretty sure it wasn't) the effect on viscosity would be quite small.

Also, if you look at the Subaru UOA, you'll also see 24ppm of moly, which seems to be a carry over from the Mobil 1 0w-40 run, where it was significantly higher.

 

[OVERKILL]

Originally Posted By: Quattro Pete
Originally Posted By: Phishin
The guy running PPE comes running to the rescue!!

Have I stated something inaccurate? Let's discuss.

I don't think you have. You've brought up the questions and points (aside from my mispost of the AMSOIL 5w-40, LOL!) I was hoping people would ask and point out

 

[drtyler]

Quattro Pete:

Mine is the first you reference.

I have used PU 5W40 several times with that car. Each time, the UOA shows around 50 ppm of moly. I have seen your VOA of PU 5W40 (with no moly). The bottles I used were dated later than your post, so I believe the formulation changed.

To all:
The electric water pump failed while driving, and the car went into limp-home mode. Then it forced a shut down. The oil likely reached significantly higher temps than normal, so that may have contributed to the viscosity loss.

The previous UOAs with that car show appropriate viscosity (looking at one now, 12.09 cSt 100C) over the same mileage. The only difference is the water pump failure.

Originally Posted By: Quattro Pete
Originally Posted By: OVERKILL
and

http://www.bobistheoilguy.com/forums/ubb..._Eu#Post3632653

This one is odd, I agree.

One strange thing is that there is moly in this UOA. PU 5w-40 does not contain moly, which might indicate he's had some leftover other oil in there or topped of with something different, and who knows what viscosity it was.


Quote:

but there are others that still ended up like this:

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=1176065

10.53cSt

That's not a Pennzoil Euro UOA.

Quote:

Or this one:
http://www.bobistheoilguy.com/forums/ubbthreads.php/topics/2253386/1

Where the 5w-40 dropped to 12.1cSt

He noted that he topped off with a quart of 5w-30 in this one.

 

[OVERKILL]

Originally Posted By: drtyler
Quattro Pete:

Mine is the first you reference.

I have used PU 5W40 several times with that car. Each time, the UOA shows around 50 ppm of moly. I have seen your VOA of PU 5W40 (with no moly). The bottles I used were dated later than your post, so I believe the formulation changed.

To all:
The electric water pump failed while driving, and the car went into limp-home mode. Then it forced a shut down. The oil likely reached significantly higher temps than normal, so that may have contributed to the viscosity loss.

The previous UOAs with that car show appropriate viscosity over the same mileage. The only difference is the water pump failure.



You wouldn't be able to link those UOA's would you? I'd like to see them. Also, regarding the overheat, while I'm sure it played a significant role in your viscosity loss, a lot of the UOA's where people attack viscosity loss are cars that are seeing track time where both fuel dilution and elevated oil temps are a reality. Shear is then blamed for the viscosity loss but often times it is accompanied by a marked reduction in flash point, which points to high levels of fuel contamination. Your results ares somewhat unique in that respect as your flashpoint didn't go down a lot but your viscosity loss was massive, which would indeed point to shear or the some other form of damage happening to the VII's in your lubricant

 

[Quattro Pete]

Originally Posted By: OVERKILL
Regarding the third, yes, I saw the quart of 5w-30, but I don't think that accounts entirely for the viscosity loss as it should be around 12.8 if we factor that in (assuming that the Ultra 5w-30 is the 10.3cSt product) and we are still well below that

The PU of that era had a starting 100c Viscosity of 13.1 cSt, according to TDS. Not sure if I did my math correctly, but taking 3.2 qts of 13.1cSt oil and 1 qt of 10.3 cSt oil, I get 12.4 cSt average. His UOA showed 12.1 cSt. After 6K miles in service in a turbo engine, I would not call it 'tremendous' shearing by any stretch of imagination.

 

[Quattro Pete]

Originally Posted By: drtyler
Quattro Pete:

Mine is the first you reference.

I have used PU 5W40 several times with that car. Each time, the UOA shows around 50 ppm of moly. I have seen your VOA of PU 5W40 (with no moly). The bottles I used were dated later than your post, so I believe the formulation changed.

Gotcha! Yeah, we haven't had a VOA done on this stuff in quite a while. Add pack could have definitely changed when SOPUS went to GTL formulation a few years back.

 

[drtyler]

OVERKILL:

Here are the numbers for the OCI previous to the massive shear down.

5261 miles on oil (PU 5W40)
AL 4
FE 11
CU 15
PB 2
MO 53
B 70
SI 4
NA 6
CA 2681
MG 39
P 879
ZN 1004

SUS @ 210F 66.8
cSt @ 100C 12.09
Flashpoint 395F
Fuel %



Originally Posted By: OVERKILL
Originally Posted By: drtyler
Quattro Pete:

Mine is the first you reference.

I have used PU 5W40 several times with that car. Each time, the UOA shows around 50 ppm of moly. I have seen your VOA of PU 5W40 (with no moly). The bottles I used were dated later than your post, so I believe the formulation changed.

To all:
The electric water pump failed while driving, and the car went into limp-home mode. Then it forced a shut down. The oil likely reached significantly higher temps than normal, so that may have contributed to the viscosity loss.

The previous UOAs with that car show appropriate viscosity over the same mileage. The only difference is the water pump failure.



You wouldn't be able to link those UOA's would you? I'd like to see them. Also, regarding the overheat, while I'm sure it played a significant role in your viscosity loss, a lot of the UOA's where people attack viscosity loss are cars that are seeing track time where both fuel dilution and elevated oil temps are a reality. Shear is then blamed for the viscosity loss but often times it is accompanied by a marked reduction in flash point, which points to high levels of fuel contamination. Your results ares somewhat unique in that respect as your flashpoint didn't go down a lot but your viscosity loss was massive, which would indeed point to shear or the some other form of damage happening to the VII's in your lubricant

 

[OVERKILL]

Originally Posted By: Quattro Pete
Originally Posted By: OVERKILL
Regarding the third, yes, I saw the quart of 5w-30, but I don't think that accounts entirely for the viscosity loss as it should be around 12.8 if we factor that in (assuming that the Ultra 5w-30 is the 10.3cSt product) and we are still well below that

The PU of that era had a starting 100c Viscosity of 13.1 cSt, according to TDS. Not sure if I did my math correctly, but taking 3.2 qts of 10.3cSt oil and 1 qt of 10.3 cSt oil, I get 12.4 cSt average. His UOA showed 12.1 cSt. After 6K miles in service in a turbo engine, I would not call it massive shearing by any stretch of imagination.




No, massive would describe the ones that are bordering on dropping into the 9.xx territory, LOL! His viscosity loss wasn't significant, just more than the 0w-40. I was using 13.5cSt for some reason, must have swapped it with the M1 0w-40 100C visc in my head.

OK, if we use 13.2cSt*3.2 quarts we get 42.24cSt, and we then add 10.3 to it and divide by 4.2, we get 12.51cSt.

However, when I owned my XT, I certainly didn't do 4.2, I did 4.5. Doesn't make a big difference, but we end up with 12.55cSt

This one ends up looking like a wash at this point. However viscosity loss wasn't high in the first place. This would show the 0w-40 and 5w-40 being roughly equal (staying in grade) if we use your numbers

 

[OVERKILL]

Originally Posted By: drtyler
OVERKILL:

Here are the numbers for the OCI previous to the massive shear down.

5261 miles on oil (PU 5W40)
AL 4
FE 11
CU 15
PB 2
MO 53
B 70
SI 4
NA 6
CA 2681
MG 39
P 879
ZN 1004

SUS @ 210F 66.8
cSt @ 100C 12.09
Flashpoint 395F
Fuel %


Thanks!

So not a lot of fuel looking at the flash point. Viscosity loss of around 1.1cSt compared to 3.2cSt when you had your overheat. My theory is that the overheat condition cooked the polymer VII's and dropped you down close to base oil visc which appears to be a light 30-weight if we figure that the PCMO Ultra 5w-30 energy conserving (non-Euro) oil has a viscosity of 10.3cSt @ 100 and the bottom limit for the 30 range is 9.3cSt.

 

[Quattro Pete]

One thing is for sure, current version of M1 0w-40 is very shear stable, especially for such high visc spread. In my limited personal experience, Pennzoil Euro 5w-40 is shear stable, but M1 0w-40 is even more impressive in this area.

 

[Quattro Pete]

Originally Posted By: OVERKILL
Originally Posted By: drtyler
OVERKILL:

Here are the numbers for the OCI previous to the massive shear down.

5261 miles on oil (PU 5W40)
AL 4
FE 11
CU 15
PB 2
MO 53
B 70
SI 4
NA 6
CA 2681
MG 39
P 879
ZN 1004

SUS @ 210F 66.8
cSt @ 100C 12.09
Flashpoint 395F
Fuel %


Thanks!

So not a lot of fuel looking at the flash point. Viscosity loss of around 1.1cSt compared to 3.2cSt when you had your overheat. My theory is that the overheat condition cooked the polymer VII's and dropped you down close to base oil visc which appears to be a light 30-weight if we figure that the PCMO Ultra 5w-30 energy conserving (non-Euro) oil has a viscosity of 10.3cSt @ 100 and the bottom limit for the 30 range is 9.3cSt.

Sounds like we've found reasonable explanations for the cause of viscosity loss in all the P Euro 5w-40 examples you've noted in your original post.

And if you look hard enough, you can find some less than ideal M1 0w-40 UOAs as well.

 

[OVERKILL]

Originally Posted By: Quattro Pete
Originally Posted By: OVERKILL
Originally Posted By: drtyler
OVERKILL:

Here are the numbers for the OCI previous to the massive shear down.

5261 miles on oil (PU 5W40)
AL 4
FE 11
CU 15
PB 2
MO 53
B 70
SI 4
NA 6
CA 2681
MG 39
P 879
ZN 1004

SUS @ 210F 66.8
cSt @ 100C 12.09
Flashpoint 395F
Fuel %


Thanks!

So not a lot of fuel looking at the flash point. Viscosity loss of around 1.1cSt compared to 3.2cSt when you had your overheat. My theory is that the overheat condition cooked the polymer VII's and dropped you down close to base oil visc which appears to be a light 30-weight if we figure that the PCMO Ultra 5w-30 energy conserving (non-Euro) oil has a viscosity of 10.3cSt @ 100 and the bottom limit for the 30 range is 9.3cSt.

Sounds like we've found reasonable explanations for the cause of viscosity loss in all the P Euro 5w-40 examples you've noted in your original post.

And if you look hard enough, you can find some less than ideal M1 0w-40 UOAs as well.

LOL! Easy QP! I think the one had some significant fuel dilution, it was the overheat example I found curious as fuel didn't explain it. I think this does

A lot of what gets pinned on shear around here often points to fuel while the examples of UOA's with high flash points (and little viscosity loss) are ignored.

And yes, you can find a number of less-than-stellar M1 0w-40 UOA's, in fact most would qualify my M5 UOA as one of those based on the fuel dilution, viscosity loss and metal uptake. But that's basically the case for any oil ever discussed on here.

My point, as noted in the OP, was to discuss viscosity loss as it often gets blamed on shear and/or the wide visc spread, yet we are seeing it here on an oil with a much narrower spread and some searching will show T6 also going out of grade, the accidental AMSOIL example...etc. All of these being 5w-40's and going further out of grade that the 0w-40's usually do

Heck, look at this UOA from aquasarium:
http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2064579

Shows Royal Purple 20w-50 ending up well into the 40-weight territory (virgin it is 20.23cSt, it ended up at 15.92cSt). Flash point was down from 425F to 375F, indicating fuel ingress.

 

[Benito]

Originally Posted By: OVERKILL
Now of course viscosity loss itself doesn't indicate an issue or that the product did not provide adequate protection and that's not the purpose of this thread, it is more to discuss causes of viscosity loss above and beyond fuel contamination as sometimes even the same model of engine will have very different viscosity loss than another fitted to a different vehicle.


Based on the replies, do you still think PU 5w40 shears more than M1 0w40?

 

[Quattro Pete]

Originally Posted By: OVERKILL
My point, as noted in the OP, was to discuss viscosity loss as it often gets blamed on shear and/or the wide visc spread, yet we are seeing it here on an oil with a much narrower spread and some searching will show T6 also going out of grade, the accidental AMSOIL example...etc. All of these being 5w-40's and going further out of grade that the 0w-40's usually do

If you say so.

But your OP's subject clearly called out PU 5w-40, and the first sentence of your post noted PU 5w-40 as having tremendous viscosity loss, and all your examples (minus the unintentional Amsoil one) also focused on PU 5w-40. So I interpreted it as you pointing to some inherent issue with PU 5w-40 specifically.

M1 0w-40 notable viscosity drop after 3K miles, not fuel related

But of course, I am a PU 5w-40 user, so anything I say or do at this point will be perceived as me trying to defend it, so I'll shut up now and let others participate in the discussion.

 

[OVERKILL]

Originally Posted By: Benito
Originally Posted By: OVERKILL
Now of course viscosity loss itself doesn't indicate an issue or that the product did not provide adequate protection and that's not the purpose of this thread, it is more to discuss causes of viscosity loss above and beyond fuel contamination as sometimes even the same model of engine will have very different viscosity loss than another fitted to a different vehicle.


Based on the replies, do you still think PU 5w40 shears more than M1 0w40?


Yes. Though I wish we had some more UOA's of it. We have literally hundreds of M1 0w-40 UOA's, and probably less than 20 PU 5w-40 UOA's