2002 Dodge Cummins Diesel; Amsoil 15w-40 AME

[billmac]

This is my second oil analysis on a vehicle that I’ve owned since new; I welcome any comments. The vehicle is a 2002 Dodge Ram 2500HD Quad Cab with a Cummins 5.9 liter, 24 valve, turbo engine and auto tranny. The truck is driven about 50-50 stop & go and freeway. The truck is not used for towing or racing. During the first sample, a Fleetguard panel type air filter was used in the OEM air filter box. I changed air filters at the start of the second sample period to a Fleetguard , P/N #AH19004. This is a very large cylinder shaped paper filter that is attached to the air induction tube and sits on a metal heat shield. The oil filter used is a Donaldson ELF full flow with no bypass filtration.

The lab was Oil Analyzers Inc. and their analysis recommendation was no corrective action required, oil is suitable for continued use. Resample at next regular interval

Previous oil and filters were changed at 6 months and/or 7500 miles. My biggest concern is the iron @18; which is a 29% increase from the previous sample. Actually, most of the wear metals increased from the previous sample. The only explanation I can come up with, other than the oil used being different, is that the ambient temps were very hot during the sample period. At one time we had 42 consecutive days of 100° plus temps. I think that I will run the Amsoil AME to about 10k miles and then change it. A friend recently gave me 4 gallons of Mobil Delvac 1. I may try that when I change the oil next time.

SAMPLE NUMBER: TWO; ONE
OIL USED: AMSOIL AME; AMSOIL HDD
15w-40; 5w-30
SAMPLE PERIOD: 05/14/06- ;10/10/05-
08/29/06; 05/14/06
AMBIENT TEMPS: 24° to 100°; 69° to 106°
MILES ON SAMPLE:5052 4979
MILES ON TRUCK: 43536 38484
MAKE-UP OIL: NONE NONE
IRON: 18 14
CHROMIUM: 1 1
LEAD: 5 4
COPPER: 9 7
TIN: 0 0
ALUMINUM: 2 2
NICKEL: 0 0
SILVER: 0 0
SILICON: 2 3
BORON: 1 1
SODIUM: 0 0
MAGNESIUM: 17 27
CALCIUM: 2888 3985
BARIUM: 4 0
PHOSPHORUS: 1265 1229
ZINC: 1462 1639
MOLYBDENUM: 0 0
TITANIUM: 0 0
VANADIUM: 0 0
POTASSIUM: 0 0
FUEL (% VOL): VIS @ 40C,cSt: NA NA
VIS @ 100C,cSt: 12.85 11.37
WATER: 0 0
SOOT/SOLIDS %WT:0.1 0.1
COOLANT: NO NO
TBN: 10.27 10.33
OXID: 23.0 14.0
NITR: 4.0 7.0
F-SOOT: 0.01 0.01

 

[TooSlick]

I think these numbers are probably characteristic for this engine, under these driving conditions. Your soot and silicon levels are both extremely low and these are the two types of contamination that most directly affect the rate of Fe wear. If you had access to some B10 or B20 biodiesel I think that would lower the Fe levels a bit - it really seems to lower ring/cylinder wear in the VW TDI engines I see using it. These two sets of data are so close that the hotter weather could easily be the difference.

It's interesting that the Series 3000, 5w-30 easily matched the heavier Amsoil 15w-40 in terms of wear rates, had better shear stability and showed less oxidation.

Amsoil claims the S3000 is their best HD diesel oil and these results support that contention....

The Mobil Delvac 1 is an excellent product and I'd consider it the main competitor to the Amsoil 15w-40.

Ted

 

[billmac]

Ted,

Thanks for your expertise. I agree, it looks like the Series 3000 oil performed better; I just wonder how it would have performed in the same ambient temps as the AME. I must admit that I am disappointed with the iron numbers on the second sample. I would have thought the heavier weight oil would have provided less wear under generally the same driving conditions, other than for the hotter temps. Also, I was surprised by the higher oxidation number. I am really wondering now if I should extend the AME out to 10k miles or go ahead and change it at 7,500.

Bill

 

[TooSlick]

These small differences could easily have been caused by the higher temps you saw while running the 15w-40.

Both these samples have plenty of life left on them and could be safely run out past 10k miles. You have almost no soot or silicon here, so I'd expect the rate of iron wear to be very low until the TBN bottoms out. That would probably be somewhere in the 20,000 mile OCI range. For example it will take many miles for this sample to thicken back up to it's original viscosity of 14.5 Cst due to soot and oxidation. So it will stay in grade for a long, long time.

Every engine is different, as are the driving conditions. So you can only really trend the one engine and determine what's normal and what's abnormal wear....

Ted

 

[Steve S]

For the price of the oil You should be able to get 10,000 miles per oil change interval The 15w/40 Amsoil is all the oil you need. The wear is very low and the numbers are about the same . The difference in the numbers is probably less than the machines tolerance.

 

[LargeCarManX2]

Everything is in the normal range and the TBN is excellent. Like Ted said, 20 K is quite possible with your set up. The 15-40 is a lot cheaper than the series 3000 and I would try 12K on the next run and sample. I am quite sure when all is said and done this will be a yearly oci for you.

 

[TeeDub]

Given the soot level of 0.1% and the extremely good air filtration, I'd at least double this service interval. I think you'll find the rate of Fe wear actually goes down over the longer OCI and the TBN will still be > 8.0.

I'd put the Amsoil bypass filter (single mount kit) on this motor and test the oil every 10k-12.5k miles. I think it's possible to get 50,000 miles on the same oil fill with this setup, in this particular motor.