Perform and Understand an Oil Analysis

Cheap_Engine_InsurancePerfect 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