Mr.T

I just read the data sheets, there are too many oils that don't hit the center of the range for a given grade with your rule-of-thumb.

Another example of an oil close to the dividing line between grade 30 and 40 is Amsoil EFO 0w-40 [European classic], it is 13.3 cst out of the bottle.

Recall that M1 5w-30 HM was 12.1 cst, and 12.5 cst is the grade 30-40 dividing line. The difference between 12.4 and 13.3 cst is nada, yet one is grade 40 and the other is grade 30. Without reading the data sheet you might start looking for an imaginary problem!

Mr.T

Cold oil level after 4200 miles, 85200 miles total. About half way into this oil change interval, no oil added. If anything, oil consumption looks slightly less with 0w-40 -- Maybe a couple ounces in 4200 miles and the color looks normal.

Mr.T

Oil: Amsoil DZF 0w-40 (diesel/gasoline rated)
Filter: NAPA PFL 41516 (oversize, same as Jeep Liberty 3.7L)
OCI: 8600 miles
Oil added during OCI: NONE (1/2 qt low on stick)
Total miles: 89700

Aluminum (AL) 2 ppm
Iron (FE) 13 ppm
Copper (CU) 14 ppm
Lead (PB) 0 ppm
Tin (SN) 0 ppm
Chromium (CR) 0 ppm
Nickel 0 ppm
Cadmium 0 ppm
Silver 0 ppm
Vanadium 0 ppm
Silicon 16 ppm
Sodium 9 ppm
TBN 3.5

Wear metals are all low, especially for an 8600 mile OCI, and it's running great. Amsoil AZF 0w-40 was installed at this OCI, which is rated for gasoline only (DZF 0w-40 is rated for both diesel & gasoline). For reference, PDF data sheets are below.


Amsoil AZF 0w-40.pdf

Amsoil DZF_5w-40_2017.pdf

jtphoto JK

Thank you for the update. I found no difference in oil consumption ( approximately 1/2 quart every 10,000klm ) between Amsoil 5W30XL and Amsoil Euro 5W40. The next oil change I am going to change to traditional weight Amsoil 10W30XL which is the weight the 3.8 was originally designed to run on.
My engine has just turned 290,000klm.

Mr.T

You're very welcome, good to hear from you. What's your typical oil change interval?

[Edit] Just noticed you implied a 10,000 km OCI. That's what happens with late night speed reading...

jtphoto JK

That is correct. In 2008 the factory warranty manual specified 10,000klm OCI.

Mr.T

The engine is running better than ever, but iron, aluminum, chrome and silicon are up in this sample. However, it's not abnormal for an engine to occasionally have some moderately higher values and I had a feeling the numbers would increase this time. Looking back at this OCI (oil change interval) here's what I suspect:

• Previous wear metal readings were low, so increases to even moderate levels are magnified by comparison. Chrome (3 ppm) was actually the only wear metal flagged "abnormal". 2 ppm is probably their abnormal limit.
• Higher silicon could mean more dirty air, which is abrasive and causes higher metal wear. This OCI had more following other Jeeps on dusty roads. Also wondering about changes to air filter efficiency as it relates to periodic cleaning of the AEM filter. Considering going back to the OEM style replaceable filter.
• There was a bad O2 sensor during this OCI and fuel trim on one bank went high for a short while. It ran rough until it failed hard, so it was likely washing the cylinder walls of oil. At 10 years and nearing 100K miles, it was a good time to replace all four O2 sensors.
• This OCI had a lot of wide open throttle runs during tuning with VCM Suite (HPTuners).

Oil: Amsoil AZF 0w-40
Filter: NAPA PFL 41516 (oversize, same as Jeep Liberty 3.7L)
OCI: 6800 miles
Oil added during OCI: NONE (almost 1 qt low on stick)
Total miles: 96500

Aluminum (AL) 11 ppm
Iron (FE) 45 ppm
Copper (CU) 14 ppm
Lead (PB) 0 ppm
Tin (SN) 0 ppm
Chromium (CR) 3 ppm
Nickel 1 ppm
Cadmium 0 ppm
Silver 0 ppm
Vanadium 0 ppm
Silicon 33 ppm
Sodium 11 ppm
TBN 3.6

jedg

I have to admit, it's pretty interesting to keep up with this on your jeep. hahaha

Mr.T

Hell, I wouldn't be able to resist reading this either. Can't be too many long term oil analyses in real time over the years, at least I haven't seen any.

As a side note, I just changed out the AEM washable filter for a OEM style NAPA Gold air filter. That silicon reading jumped too much, and there was some light dust in the intake. I have a differential pressure monitor on the filter housing -- Did a quick run to 5K RPM at full throttle to see if there's any difference between the AEM and NAPA. Both were ~10" water differential, so as far as filter restriction they're fairly equal.

Rednroll

Yes, this is incredible data. Unfortunately, for myself it's the 1st time I've read "parts" of it. Full Disclosure: I read your 1st post, scanned down some and then jumped to the end.

What I was curious about is if you ever ran an analysis on your oil prior to use? Or is it a known assumption that prior to use things like 3PPM AL, 12PPM CU, 18PPM Si, etc would all be 0PPM prior to use? I guess what I'm trying to determine is what parts did the oil pick up from use, and which parts may have already been present as part of the new oil mixture?