Another UOA = Used Oil Analysis, 07 Yukon Denali 6.2L w183k miles, Amsoil 0w-20 w/8.5k miles

[donjetman]

Here's the lastest UOA for our 07 Yukon Denali w/all aluminum 6.2L L92 (non-AFM) w183k miles running premium gasoline.

This oil was installed April of 2022. It was Amsoil ASM 0w-20. Full flow oil filter was Fram Ultra XG10575. Bypass oil filter is Amsoil EaBP90.

DIC: 31% remaining. Averaged 17.4 mpg and 47 mph. 50% hwy, 50% local. Burned 491 gals in 182 hrs = 2.7 gph.

Samples #1 & 2 are the same load of Amsoil ASM 0w-20 with a 1/2 qt of makeup oil added between samples
Sample #3 is Kirkland 5w-30
Samples #4 & 5 are different loads of Mobil Delvac1 ESP 5w-30
Sample #6 is Mobil Delvac1 ESP 5w-40

Between samples #5 & 6 a plastic heater hose t-fitting broke which resulted in a short overheat event.

This was my first time to run any 0w-20 oil in anything. Gas mileage locally is 16.0 mpg and 19.0 mpg on the hwy. This is a noticeable improvement. I'm getting 20-30 more miles per tank (25.5 gals). Or it could be that I changed all 4 O2 sensors. I drive the speed limit (conservatively), no towing, no hot rodding.

I changed the oil to HPLoil.com performance synthetic 0w-20, and the full flow filter to Fram Titanium FS10575. The bypass was drained and reinstalled for its fourth run.

What say you?

 

[swathdiver]

Looks good Don! How are you determining city vs highway usage?

 

[donjetman]

@swathdiver .
We don't really do much "city". We do "local" rual driving where we live (out near the sticks). Sometimes I get stuck in stop and go traffic during rush hr, so we're not that far out.

Our "hwy" driving is mainly the 1000 miles each way between our TX and CO mtn home. It easy for me to remember how many times I've done that.

Recently (since this UOA and switching too HPLoil.com 0w-20) we've did a "hwy" trip to the CO mtn home (10,000' asl) and back (1000' asl). We fought a headwind going and got 17.4 mpg. We had a tailwind coming back and got 19.8 mpg. Averaged 66 mph each way.

 

[swathdiver]

I had always wondered if there was a way to determine the amount of city versus highway driving time with each tank of gas. I could calculate the mph easy enough but on average, over time, how much time was spent doing each?

I went to fueleconomy.gov again and went to the section where they calculate mpgs and they use 21.2 mph for 100% city driving and 48.3 mph for 100% highway driving. So adopting their logic, I made a chart in Excel and use a formula to interpret the city vs hwy useage based on the mph per tank of gas. Then mpg and gph charts for each were made.

So having said all of that, your 47 mph average works out to 95.2% highway driving.

 

[donjetman]

I had always wondered if there was a way to determine the amount of city versus highway driving time with each tank of gas. I could calculate the mph easy enough but on average, over time, how much time was spent doing each?

I went to fueleconomy.gov again and went to the section where they calculate mpgs and they use 21.2 mph for 100% city driving and 48.3 mph for 100% highway driving. So adopting their logic, I made a chart in Excel and use a formula to interpret the city vs hwy useage based on the mph per tank of gas. Then mpg and gph charts for each were made.

So having said all of that, your 47 mph average works out to 95.2% highway driving.

It's easy math: Divide miles by hours. DIC provides the info.

It's a 3rd vehicle (2 drivers). We only drive it "locally" if we're going 30 miles or more.

About 60% of our TX - CO - TX trips are done in the Yukon, the other 40% are done in our Prevost bus/mh.

I'm thinkin about replacing the Yukon with a C5 Z06 Corvette.

 

[5StarCustmSolutns]

Here's the lastest UOA for our 07 Yukon Denali w/all aluminum 6.2L L92 (non-AFM) w183k miles running premium gasoline.

This oil was installed April of 2022. It was Amsoil ASM 0w-20. Full flow oil filter was Fram Ultra XG10575. Bypass oil filter is Amsoil EaBP90.

DIC: 31% remaining. Averaged 17.4 mpg and 47 mph. 50% hwy, 50% local. Burned 491 gals in 182 hrs = 2.7 gph.

Samples #1 & 2 are the same load of Amsoil ASM 0w-20 with a 1/2 qt of makeup oil added between samples
Sample #3 is Kirkland 5w-30
Samples #4 & 5 are different loads of Mobil Delvac1 ESP 5w-30
Sample #6 is Mobil Delvac1 ESP 5w-40

Between samples #5 & 6 a plastic heater hose t-fitting broke which resulted in a short overheat event.

This was my first time to run any 0w-20 oil in anything. Gas mileage locally is 16.0 mpg and 19.0 mpg on the hwy.

What say you?

I say WOW....impressive
I've no idea what levels of these elements would be considered low, acceptable, or excessive when testing 3/4 life motor oil? I found this trying to get some feedback on making the engine oil switch from Mobil 1 to Amsoil and Trans Oil switch from Valvoline to Amsoil... But just based off the results, it looks like each of them was strong in different areas?

Would have to think you'd want aluminum and iron to be low in an L92, same as I would in my all alum LC9?

I originally thought the Kirkland looked the best overall, but I think the Amsoil changed at shorter intervals may be a touch better??

Bottom line: I pray daily to grow into a man this thorough and meticulous! Nice work

 

[donjetman]

I say WOW....impressive
I've no idea what levels of these elements would be considered low, acceptable, or excessive when testing 3/4 life motor oil? I found this trying to get some feedback on making the engine oil switch from Mobil 1 to Amsoil and Trans Oil switch from Valvoline to Amsoil... But just based off the results, it looks like each of them was strong in different areas?

Would have to think you'd want aluminum and iron to be low in an L92, same as I would in my all alum LC9?

I originally thought the Kirkland looked the best overall, but I think the Amsoil changed at shorter intervals may be a touch better??

Bottom line: I pray daily to grow into a man this thorough and meticulous! Nice work

Engine suffered an overheat event (Broken heat hose plastic T) Dec of 2019, should have change oil immediately. Hi iron etc afterwards.

 

[Dustin Jackson]

In an aluminum motor, where does the iron come from?

 

[donjetman]

In an aluminum motor, where does the iron come from?

steel/iron sleeves

 

[dkad260]

I don't know enough about an OCA to determine what is good or bad, but I'm curious why you chose a 20wt oil for a 180K motor over the OE spec 30 wt?

Does the manual say a 20wt is ok for that year engine?

I know Amsoil is good stuff, I'm just thinking on the shear over time by beginning with a 20wt oil over a 30wt.

Is your Yukon AWD or RWD? Tires properly inflated?

New upstream O2 sensors over worn sensors can play a part with fuel economy.

Another thought, if you compare highway MPG in the dead of winter as opposed to spring/summer, I agree, wind plays a big part. Cold, dense air is harder to push through, if you have flown light planes you know what I mean.

Overall it looks good, but if the iron is up over your other oil changes, what comes to mind is also the crankshaft journal, along with the before mentioned cylinder sleeve.

Again, above my pay grade, by personal thought is to stay with a 30wt...but that's just me.