My UOA 5w20 vs 5w30. Any guesses?

[DrDusty86]

I switched My car over to 5w20 a while ago. It is almost time for another UOA.
Criteria/conditions: Same type of filter-K&N, Same brand -RP, Will be close to same milage and hours, 0 oil added, Texas heat of 100*+, This will be as close as I can make it to compare them.
Any Guesses on which one will show less wear? I will have it sent off in about 3 weeks
Car: Escort ZX2 2.0 DOHC ZTEC motor. Milage 202k with synthetics since 48k.
Dusty

 

[electrolover]

wonder if the 30w is going to give better wear numbers...

 

[tinmanSC]

The increase or decrease in wear will probably be within the margin of error. I doubt you will see any change.

 

[DrDusty86]

I can't wait....really. The 5w30 UOA is already on this site.. It had 5700 miles AND 110 Idling engine hours on it. Iron=8ppm and TBN was 6.5... I can't remember the whole report and its in my maintenance record folder.

 

[bepperb]

If the 5-30 is 8, I'm hoping the 5-20 is 9. That way we can get 100+ pages of people arguing about it.

Then again, if it came in a 7 then I think it could be a long thread too.

 

[hate2work]

Originally Posted By: bepperb
If the 5-30 is 8, I'm hoping the 5-20 is 9. That way we can get 100+ pages of people arguing about it.

 

[DrDusty86]

True... But if its that trivial, I will run the 5w20. I have 22Qts of 5w20 I got at an AWESOME price so I'm kinda stuck with it. It will be interesting.

 

[Quattro Pete]

Originally Posted By: DrDusty86
True... But if its that trivial,

It is trivial, and a $20 UOA is not going to tell you anything about which oil is better.

 

[walk23]

My bet is on the 5W-30. Keep us posted.

 

[DrDusty86]

Pete,
I know... I know... It MAY OR MAY NOT prove the thicker is better..

The TSB from ford says I can use 5w20, so they should have done the testing to prove for this particular application the thinner oil is the best choice. Right???

 

[Quattro Pete]

Originally Posted By: DrDusty86
Pete,
I know... I know... It MAY OR MAY NOT prove the thicker is better..

It WILL NOT prove.

 

[DrDusty86]

AWW, Shucks Pete,
You are telling me I'm gonna waiste $13... Why even bother with it then??

 

[Rob_Roy]

Given the variability of UOA's, I doubt you will see any significant difference.

 

[Jim Allen]

Dusty- I doubt any significant difference and as long as you use the same lab, you'll get reasonably close results. Your test, at least, will provide pretty much an oranges to oranges situation. Basically the same oil and basic formulation, just a change in viscosity. The thing is that comparing a few PPM here or there don't mean nuthin'. Say the Iron is 10 PPM on the 5W30 and 14 PPM on the 5W20. The "thick" crowd may be crowin', struttin' and sayin', "See I toldyaso!" If the opposite happens, the thin crowd might do the same. In reality, the difference is both inconsequential and within the margin for error (and there IS a margin for error no matter the lab). For everyone, remember that it's PARTS PER MILLION and you need a big change for it to be statistically significant. A few extra or fewer cold starts could account for a small change of PPM.

My contention is that, for most engines, there isn't much difference with the 5W20-5W30 range. The lighter oil gives you a few benefits and the heavier oil has some too but they largely cancel out. We've discussed this ad nauseum. In special situations, one oil or the other might have more benefit or better suitability but for most of us, and our engines, it's just a tossup. "Normal use" is well within the range of either oil's capability. FoMoCo knows this.

I had some utterly fantastic UOAs on 5W20 RP in my 5.4L V8. I expect the same with MC 10W30 (not changed for any reason other than consolidating all my oil to one type in a "fleet" of trucks, cars, tractors and small engines).

 

[friendly_jacek]

if you are serious about it, why don't you take apart your oil filter and examine matal particle inside with a microscope. The UOA will tell you next to nothing about wear.

 

[OldCowboy]

Originally Posted By: friendly_jacek
The UOA will tell you next to nothing about wear.


I'm curious. If you really believe this, why are you on BITOG?? After all, the main page of GITOG states in the first paragraph, "By analyzing a sample of used engine oil, you can determine the wear rate, and overall service condition of an engine, along with spotting potential problems and imminent failure before it happens."

 

[Doug Hillary]

Hi,
OldCowboy - you quoted this paragraph:

"By analyzing a sample of used engine oil, you can determine the wear rate, and overall service condition of an engine, along with spotting potential problems and imminent failure before it happens."

IME it is not as clear as it sounds. UOAs are simply a tool in component management and are better at quantifying the CONDITION of the lubricant than most other things outside Lab conditions. Skilled practictioners can learn much from UOAs - the most from trending an engine or an engine family over time and distance. In reality a lot of time and a lot of distance

 

[Gene K]

If you saw sustained sump temps above 250F then the 30 weight will be slightly better. If not the 20 weight will be slightly better. Although without controlled test conditions I imagine any difference will be lost in the noise.

Just my opinion. That and a buck will buy you a cheap cup of coffee.

 

[OldCowboy]

Originally Posted By: Doug Hillary
Hi,
OldCowboy - you quoted this paragraph:

"By analyzing a sample of used engine oil, you can determine the wear rate, and overall service condition of an engine, along with spotting potential problems and imminent failure before it happens."

IME it is not as clear as it sounds. UOAs are simply a tool in component management and are better at quantifying the CONDITION of the lubricant than most other things outside Lab conditions. Skilled practictioners can learn much from UOAs - the most from trending an engine or an engine family over time and distance. In reality a lot of time and a lot of distance


Hi Doug,

I understand that UOAs are better at quantifying the condition of the lubricant. However, I disagree with the previous poster's contention that UOAs will tell you next to nothing about wear.

 

[Doug Hillary]

Hi,
OldCowboy - You said this:

"However, I disagree with the previous poster's contention that UOAs will tell you next to nothing about wear."

Sadly for the average BITOG Member using single pass UOAs in normal applications (typical private use cycle) and not obtaining other data such as the PQ Index - his statement is substantially correct