UOA question: towing vs not-towing

[meborder]

does anyone have, or has anyone seen a pair of UOA's on the same vehicle, with the only known variable being towing vs. non-towing miles.

to the point....

my first UOA had frigid cold and 1,000 miles of towing and came back with relatively high metals.

my next UOA had summer temps, no towing, and showed very good metals.

so ... were the high metals from the frigid cold, or the towing, or something else.

i did a UOA on a different vehicle during the same frigid cold which showed normal metals, making me think that the towing (higher RPM and higher load) was responsible for the higher metals.

just wondering if anyone has seen a somewhat back-to-back comparison.

I missed my chance on a back-to-back frigid cold analysis without the towing this year.

thanks!

 

[Ducman]

It's inevitable that one will get higher wear metals when towing.

The machinery is after all, under increased strain and that's why towing is deemed to be one of "the classic severe service conditions" by all vehicle manufacturers.
It applies to responsible oil manufacturers as well.
Just have a look at the Amsoil website and check out the oil of choice for your vehicle.
Usually, somewhere in the blurb there will be a disclaimer in terms of service life, with a corresponding downgrade of the oil's service life when towing, racing, engine modifications/tuning, short trips(under 16 Kms), dusty conditions, etc, etc.

I think it's only fair to add extreme cold conditions onto the list for good measure, as the oil rarely if ever comes up to the correct operating temperature.

 

[CarbonSteel]

Originally Posted By: meborder
does anyone have, or has anyone seen a pair of UOA's on the same vehicle, with the only known variable being towing vs. non-towing miles.

I have experienced both conditions that you have described. I have towed about 45% of the miles on my FX4 and some of these miles are in the cold of Colorado and each time I tow I see an increase of wear metals--perhaps a bit more in the cold. Take a look at UOAs No. 4, 10, 16, 19, and 20. All of these had a fair amount towing (either in the heat or cold) versus the others which had less towing (some not at all). In particular, look at No. 4 versus 5, 6, and 7--No. 4 had lots of towing in the cold (Houston to Chicago and back) and 5, 6, and 7 had none.

 

[tig1]

Show us the numbers between the two.

 

[meborder]

These are the UOA's I have on my Expedition:


Code:


OIL Trop 5w30 NAPA 5w20

Artic Synthetic

SynBlend



MILES IN USE 4,989 6,447

MILES 125,086 114,429

SAMPLE TAKEN 10/23/14 06/01/14





Metals (ppm)

IRON 10 45

CHROMIUM
LEAD
COPPER 1 2

TIN
ALUMINUM 4 22

NICKEL
SILVER
TITANIUM
VANADIUM



Contaminants (ppm)

SILICON 8 10

SODIUM 17 278

POTASSIUM


Additives (ppm)

MAGNESIUM 14 118

CALCIUM 2044 1792

BARIUM
PHOSPHORUS 690 627

ZINC 761 730

MOLYBDENUM 15 6

BORON 70 9



Contaminants

WATER
Coolant No No



Physical Tests

Visc (cSt 100C) 8.9 9.0



TBN (mgKOH/g) 2.6 2.5


Compare the NAPA Synthetic above with the one from our Subaru below. Operating conditions were the same between the two vehicles except the towing:
2002 Subaru Outback H6

Code:


OIL NAPA 5w20

Synthetic





MILES IN USE 5,500

MILES 115,500

SAMPLE TAKEN 6/01/14





Metals (ppm)

IRON 6

CHROMIUM
LEAD
COPPER 1

TIN
ALUMINUM 2

NICKEL
SILVER
TITANIUM
VANADIUM



Contaminants (ppm)

SILICON 4

SODIUM 217

POTASSIUM 6



Additives (ppm)

MAGNESIUM
CALCIUM 1832

BARIUM
PHOSPHORUS 554

ZINC 661

MOLYBDENUM 4

BORON 20



Contaminants

WATER
Coolant No No



Physical Tests

Visc (cSt 100C) 9.5



TBN (mgKOH/g) 2.3


Now I realize one can't infer much from one vehicle to another, but what I got out of it was the the extreme cold that year didn't hurt the Subaru one bit, whereas the expedition had notably higher metals.

 

[dustyroads]

Meborder, those are considerably different wear numbers. I'm curious if you had that expedition long before that Napa oci and doing good maintenance or if you bought it shortly before that oci and it was a neglected vehicle.

Towing, temps and oci length are noted, but still seems like a lot of extra metals showing in that towing oci. I doubt it was related to the napa oil. It did great in the subie.

Maybe you were doing some serious towing? I seem to recall last year you mentioned pulling a trailer that was really big and working the engine hard (?).

 

[Smokescreen]

It's tough to compare when you used two totally different oils both manufacturer and weight, instead of towing being the only variable you have 3 maybe 4 different variables to contribute to the numbers.

 

[meborder]

Originally Posted By: 2010_FX4
Originally Posted By: meborder
does anyone have, or has anyone seen a pair of UOA's on the same vehicle, with the only known variable being towing vs. non-towing miles.

I have experienced both conditions that you have described. I have towed about 45% of the miles on my FX4 and some of these miles are in the cold of Colorado and each time I tow I see an increase of wear metals--perhaps a bit more in the cold. Take a look at UOAs No. 4, 10, 16, 19, and 20. All of these had a fair amount towing (either in the heat or cold) versus the others which had less towing (some not at all). In particular, look at No. 4 versus 5, 6, and 7--No. 4 had lots of towing in the cold (Houston to Chicago and back) and 5, 6, and 7 had none.


thanks for the spreadsheet.
i'll have to print that out and make some comparisons (too big to fit on the screen)
very complete! i have a unique appreciation for a well thought-out spreadsheet

 

[meborder]

Originally Posted By: dustyroads
Meborder, those are considerably different wear numbers. I'm curious if you had that expedition long before that Napa oci and doing good maintenance or if you bought it shortly before that oci and it was a neglected vehicle.

Towing, temps and oci length are noted, but still seems like a lot of extra metals showing in that towing oci. I doubt it was related to the napa oil. It did great in the subie.

Maybe you were doing some serious towing? I seem to recall last year you mentioned pulling a trailer that was really big and working the engine hard (?).


At that time i had purchased the truck about 6 months before. At the end of that oil change (NAPA Syn) i had put 10,000 miles on the truck since purchase. The NAPA oil was the first oil that i put in since purchase. The oil looked pretty fresh when i bought it, but i changed it at about 3,000 miles after purchase not knowing what they had in there or how long.

previous history before that is completely unknown. other than it was a new jersey vehicle before i got it, i don't know much (did get a carfax, but that only tells you so much)

During the NAPA OCI it was bitterly cold at the beginning of that OCI, but after the weather broke i hauled a 6x12 enclosed trailer about 500 miles empty and back about 500 miles full. Full being relative, i'd estimate the weight under 3,000 lbs. During the tow i had to run out of overdrive for most of the trip and got a trip average of about 11.2mpg. That trailer just seems to catch a lot of wind making it pull hard. not real heavy though. Never once did it work hard enough to downshift to second, though. RPMs while towing would have been between 2500 and 2800 rpm depending on speed (65-70.... after 6 hours towing with a toddler and mom in the back seat i kicked it up a notch)

if there's any interest, here's a thread i posted on ford-trucks.com:
http://www.ford-trucks.com/forums/1304445-900-mile-tow-coming-up.html#post14207567 (i skipped ya' ahead to the towing part)

here's the trailer:

would a 3,000 mile OCI be enough to flush out previous neglect? maybe it took another long run with a synthetic to really flush it out?
IDK ... interesting thoughts.

 

[meborder]

Originally Posted By: Smokescreen
It's tough to compare when you used two totally different oils both manufacturer and weight, instead of towing being the only variable you have 3 maybe 4 different variables to contribute to the numbers.


i'm sorta with ya, but here's how i was looking at it.

i've got a side by side UOA with Napa Synthetic of the recommended viscosity for two different vehicles with nearly identical milage in nearly identical weather conditions aside from the long tow.

and then i've got two UOA's in the same vehicle with vastly different conditions and different oils.

hard to make much comparisons, is suppose, but it's all i got to work with.

 

[dustyroads]

I wondered if maybe it had been somewhat neglected, as in crazy long oci's and built up wear metals that were still carrying over or maybe it sat for an extended period and got a little rusty.

It was probably just a case of cold starts during the winter and then towing later on. I don't have many test results of my own from cars/pickups, etc. However, I have many years of samples on my big trucks and there's always a slight increase in aluminum, iron and sometimes chromium on the winter oci's. Nothing drastic but I spend most of winter in the north and get lots of really cold starts thrown in.

The important thing is, your last sample looks great and the engine seems to be in good shape. I may have been needlessly surprised by the first sample.