Perfect Oil Change:
Cheap Engine Insurance
(Diesel Power, December 2011
Text and Photography by Mike McGlothlin)
Diesel engines are large investments. And because they’re an upgrade option on our trucks, SUVs, and passenger cars, they cost more. How do you protect that investment? One easy way to catch a glimpse of your engine’s overall health is through an oil analysis. Most oil analyzers can test for wear metals (elements like iron, aluminum, and copper) to see if things like piston rings, pistons, bearings, or valvetrain components are breaking down. Particulate count tests, which clue you into what may be contaminating your engine’s oil (be it soot, coolant, fuel, or dirt), are also the norm.
The best part about an oil analysis is that it’s cheap insurance. It lets you know if your maintenance intervals are adequate, which contaminants are getting in (so you can stop them), and it can give you a rough timeline of how soon you need to overhaul an engine. After uploading Green Diesel Engineering’s Eco tune to our ’05 Jeep Liberty CRD (which effectively disabled EGR) and adding a K&N air filter, we had a used engine oil sample analyzed. When compared to our previous (EGR-laced) oil analysis, we saw several improvements in the health of our oil. Check out the results below to see why you should be taking a closer look at your engine’s lifeblood.
Before and After Oil Analysis (Oil Analysis Compared) Wear metals (PPM) |
|||||||||||||
CU
|
FE
|
CR
|
AL
|
SN
|
SI
|
NA
|
K
|
MO
|
CA
|
MG
|
ZN
|
P
|
|
EGR
|
2
|
16
|
1
|
4
|
0
|
11
|
4
|
3
|
57
|
804
|
1,170
|
1,260
|
1082
|
NO EGR
|
2
|
15
|
1
|
5
|
1
|
8
|
6
|
2
|
62
|
789
|
1,179
|
1,236
|
1,058
|
*We could attribute the drop in Si (Silicon) to the improved filtration our K&N air filter provides.
Wear Metals Glossary |
||
Symbol
|
Element
|
What it can mean for your engine |
CU
|
Copper | Indicative of bear wear (i.e. main bearings) |
FE
|
Iron | Indicative of component wear such as piston rings, connecting rods, crankshaft, engine block |
CR
|
Chromium | Indicative of component wear such as piston rings |
AL
|
Aluminum | Indicative of component wear such as bearings, bushings |
SN
|
Tin | Indicative of valvetrain wear |
SI
|
Silicon | Can be found due to ingested dirt via intake or other external sources, or from de-foemant additive in oil |
NA
|
Sodium | Used as additive in some oils, cooling water inhibitor |
K
|
Potassium | Cooling additive in oil |
MO
|
Molybdenum | Anti-wear additive (Found in high-strength steel alloys) |
CA
|
Calcium | Detergent/dispersant additive in oil |
MG
|
Magnesium | Detergent/dispersant additive in oil |
ZN
|
Zinc | Anti-wear element |
P | Phosphorus | Anti-wear element |
*Elements found in oil are measured in parts per million (ppm) — which is a very small amount.
It would take 10,000 ppm to make up 1 percent of the oil.
Oil Condition/Particle Count Glossary |
||
Acronym
|
Particle/ Chemical Reaction
|
What it means |
ST
|
Soot
|
Particulate matter found in used engine oil (much higher with active EGR) |
OXE
|
Oxidation
|
The slow breakdown of base oil molecules (heat will speed up the ozidation process, resulting in less lubrication) |
NIT
|
Nitration
|
When nitrogen molecules break down to two atoms, they react the oxygen to form NOx; higher NOx levels rapidly accelerate oxidation of oil |
SUL
|
Sulfation
|
Sulfer-based acid formed by burning diesel fuel, sulfur oxides and water, most exit via engine exhaust, but some enter engine blow-by. |
W
|
Water
|
Water tests are either p (positive) or N (negative) |
A
|
Antifreeze
|
Antifreeze tests are either p (positive) or N (negative) |
F
|
Fuel
|
Fuel tests are either p (positive) or N (negative) |
PFC
|
Percent Fuel Content
|
What percentage of fuel is contaminating the oil |
V100
|
Viscosity test
|
Viscosity is tested at 100 degrees C |
*Ct/ml equates to the particle count (ct) contaimed per mililiter (ml).
Before and After EGR (Oil Analysis Compared)Oil Condition/Particle Count (CT/ML) |
|||||||||
ST
|
OXI
|
NIT
|
SUL
|
W
|
A
|
F
|
PFC
|
V100
|
|
EGR
|
56
|
16
|
10
|
23
|
N
|
N
|
N
|
1.67
|
14.4
|
NO EGR
|
4
|
15
|
8
|
17
|
N
|
N
|
N
|
.64
|
13.8
|
Test Details
- Our oil analyses were performed by Altorfer CAT in Cedar Rapids, Iowa
- Both used oil samples had approximately 4,000 miles on them
- Both tested samples were Shell Rotella T6 5W-40 Synthetic
- Article was written by Altorfer customer Mike McGlothlin