5w-40 oil analysis results
05-11-2013, 08:18 AM
#31
JK Junkie
05-11-2013, 09:40 AM
#32
JK Junkie
Thread Starter
Wow, you seem to have an extremely rigid attitude about complying with manufacturer's recommendations. It's just oil, not religious doctrine.
There is more to the manufacturer's recommended oil viscosity than simply low engine wear and low oil consumption in a wide range of operating conditions -- This isn't the 1960's. Automobile makers now have the legalities and economic pressures to achieve better CAFE results under lab conditions.
The above 5w-40 analysis results for wear metals with 8600 miles on the oil, and zero oil added (no dilution with new oil), speaks for itself. Think about it -- If the oil was "WRONG", there would be evidence in the analysis for wear metals, but to the contrary, the wear metals are quite low taking the high mileage on the oil into account.
Regarding the 5w-40 oil: Lower wear, less oil consumption, less blow-by, and better protection at extreme operating conditions (high temperatures, low RPM lugging, towing). Less spark knock, and less combustion chamber carbon build-up, are directly related to less oil consumption and less blow-by.
There is more to the manufacturer's recommended oil viscosity than simply low engine wear and low oil consumption in a wide range of operating conditions -- This isn't the 1960's. Automobile makers now have the legalities and economic pressures to achieve better CAFE results under lab conditions.
The above 5w-40 analysis results for wear metals with 8600 miles on the oil, and zero oil added (no dilution with new oil), speaks for itself. Think about it -- If the oil was "WRONG", there would be evidence in the analysis for wear metals, but to the contrary, the wear metals are quite low taking the high mileage on the oil into account.
Regarding the 5w-40 oil: Lower wear, less oil consumption, less blow-by, and better protection at extreme operating conditions (high temperatures, low RPM lugging, towing). Less spark knock, and less combustion chamber carbon build-up, are directly related to less oil consumption and less blow-by.
Last edited by Mr.T; 05-11-2013 at 09:55 AM.
05-11-2013, 10:32 AM
#33
JK Freak
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Wow, you seem to have an extremely rigid attitude about complying with manufacturer's recommendations. It's just oil, not religious doctrine.
There is more to the manufacturer's recommended oil viscosity than simply low engine wear and low oil consumption in a wide range of operating conditions -- This isn't the 1960's. Automobile makers now have the legalities and economic pressures to achieve better CAFE results under lab conditions.
The above 5w-40 analysis results for wear metals with 8600 miles on the oil, and zero oil added (no dilution with new oil), speaks for itself. Think about it -- If the oil was "WRONG", there would be evidence in the analysis for wear metals, but to the contrary, the wear metals are quite low taking the high mileage on the oil into account.
Regarding the 5w-40 oil: Lower wear, less oil consumption, less blow-by, and better protection at extreme operating conditions (high temperatures, low RPM lugging, towing). Less spark knock, and less combustion chamber carbon build-up, are directly related to less oil consumption and less blow-by.
05-11-2013, 11:08 AM
#34
JK Junkie
Thread Starter
If it's crudded up because of lot's of blow-by gasses and oil mist, change it out. I'd bet a lot of PCV's get changed out even though they are working fine. The PCV for the 3.8 can be very tight and hard to remove, spark plug wire pliers is what I've used to pull it.
It's tough to describe, but the design for the PCV on the 3.8 has sort of a catch-can for oil mist built-in. The large vertical rubber hose above the PCV (downstream flow relative to the valve) will tend to collect oil droplets, and on my 2008 there is a small notch/hole in the PCV valve that would allow collected oil to drain back when the engine is off (no manifold vacuum). I've seen a PCV without this drain-back notch/hole, but recommend using one that has it. Maybe Chrysler had different PCV's, or maybe some manufacturer's just omitted the hole -- Don't know for sure, but the little hole for drainback made good sense to me.
It's tough to describe, but the design for the PCV on the 3.8 has sort of a catch-can for oil mist built-in. The large vertical rubber hose above the PCV (downstream flow relative to the valve) will tend to collect oil droplets, and on my 2008 there is a small notch/hole in the PCV valve that would allow collected oil to drain back when the engine is off (no manifold vacuum). I've seen a PCV without this drain-back notch/hole, but recommend using one that has it. Maybe Chrysler had different PCV's, or maybe some manufacturer's just omitted the hole -- Don't know for sure, but the little hole for drainback made good sense to me.
12-29-2014, 06:39 PM
#35
JK Junkie
Thread Starter
Another excellent 5w-40 analysis...
Aluminum (AL) 1 ppm
Iron (FE) 16 ppm
Copper (CU) 33 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 10 ppm
Sodium 9 ppm
Viscosity @ 100C 14.8 cSt
TBN 4.5
Amsoil DEO 5w-40 (switched from AFL 5w-40 European oil). EA15K51 oil filter. Total miles using 5w-40 are about 30K. Total miles on Jeep are a bit over 40K -- Engine is fairly new and tight, no oil added during the OCI (oil change interval).
Iron (FE) 16 ppm
Copper (CU) 33 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 10 ppm
Sodium 9 ppm
Viscosity @ 100C 14.8 cSt
TBN 4.5
Amsoil DEO 5w-40 (switched from AFL 5w-40 European oil). EA15K51 oil filter. Total miles using 5w-40 are about 30K. Total miles on Jeep are a bit over 40K -- Engine is fairly new and tight, no oil added during the OCI (oil change interval).
11-30-2015, 08:57 PM
#36
JK Junkie
Thread Starter
5w-40 oil - 8300 mile OCI, good analysis numbers again!
8300 miles on the oil this time (5w-40 Amsoil DEO), and no makeup oil added. The wear metal numbers are very low, especially with 8300 miles on the oil, and the trend is toward lower numbers. The results speak for themselves, especially in concert with the 47K miles worth of sample data on this engine in this thread. 
Aluminum (AL) 2 ppm
Iron (FE) 13 ppm
Copper (CU) 21 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 12 ppm
Sodium 10 ppm
TBN 3.8
Amsoil DEO 5w-40 (diesel/gasoline rated). EAO34 oil filter (oversize, fits 2008 Jeep Liberty 3.7L). Total miles using 5w-40 are about 47K. Total miles on Jeep are a bit over 57K. Usage was very typical: Lots of short trips (4 miles) to town, plus long trips and 4LO for vacations.
Aluminum (AL) 2 ppm
Iron (FE) 13 ppm
Copper (CU) 21 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 12 ppm
Sodium 10 ppm
TBN 3.8
Amsoil DEO 5w-40 (diesel/gasoline rated). EAO34 oil filter (oversize, fits 2008 Jeep Liberty 3.7L). Total miles using 5w-40 are about 47K. Total miles on Jeep are a bit over 57K. Usage was very typical: Lots of short trips (4 miles) to town, plus long trips and 4LO for vacations.
Last edited by Mr.T; 12-15-2015 at 03:46 PM. Reason: Added oil filter info
12-01-2015, 12:41 AM
#37
JK Junkie
Going with this on the next oil change. 180,000 on my rig, No spark knock when load is on would be awesome. I went from 5w20 to 5w30, it helped a bit, but I am going to goto 5w40 next oil change to see how that works.
12-01-2015, 09:04 AM
#38
JK Junkie
Thread Starter
12-04-2015, 03:15 AM
#39
JK Junkie
There's no down side to 5w-40, not even a detectable change in MPG. It will probably reduce any oil consumption, which can promote spark knock and carbon deposits. Zero audible spark knock on mine now, but when I first bought it (used with 10 K miles) it did have some noticeable spark knock. I believe the previous owner did all short trip slow driving, and it probably took a while to burn off the carbon deposits -- 5w-40 may have helped as well. Occasionally driving full throttle at 4-5k RPM up hills is good for engines!
12-04-2015, 11:22 AM
#40
JK Junkie
Thread Starter
Yeah, Mine is used, and used pretty hard. Not abused but used. I do get spark knock, I tried supreme fuel and worked a bit, but I would like to go back to regular gas, for the extra burn. I think I'm going to get some 5w40 to see if My oil consumption goes down as well as spark knock. If it does, I will switch to amsoil 5w40 then. Try the cheap stuff first to see how she goes! ha ha.
You might want to consider "Chrysler Combustion Chamber Cleaner (CCCC)". Here's a video on it: https://www.youtube.com/watch?v=6EZmYyrAU58 Near the end, he's killing the engine with whole bunch of it in the intake, then letting it soak for a while to loosen up carbon/oil deposits. I've used CCCC on a couple cars; It isn't a miracle cure, but it does what it claims. If doing both CCCC and an oil change, do the CCCC first so that whatever small amount leaks by the piston rings is removed with the old oil.
Last edited by Mr.T; 12-04-2015 at 12:04 PM.