K 3500 Truck 4WD V8-6.5L DSL Turbo VIN S (1999)
Fuel: Testing and Inspection
Fuel Quality Diagnosis
Fuel quality may cause driveability problems such as hesitation, lack of power, stall, no start, etc.
For best results, use Number 2-D diesel fuel year-round (above and below freezing conditions) as oil companies blend Number 2-D fuel to address
climate differences. Number 1-D diesel fuel may be used in very cold temperatures (when it stays below 18°C (0°F); however; it will produce a power
and fuel economy loss. The use of Number 1-D fuel in warm or hot climates may result in stalling, poor starting when the engine is hot and may damage
the fuel injection system.
Specific Gravity Testing
The fuel quality hydrometer provides a general indication of fuel quality and should not be considered scientifically accurate.
1. Drain the fuel filter housing by following the steps below:
1.1. Stop the engine.
1.2. Place a container under the water drain valve exit hose at the left front side of the engine.
1.3. Open the drain valve.
1.4. Use a scan tool and command the fuel lift pump ON.
1.5. Fill a 1 liter (0.946 quart) container with a sample of fuel.
1.6. Close the drain valve.
2. Obtain a fuel quality hydrometer (J 38641-B).
3. Fill the hydrometer with the fuel sample by doing the following:
3.1. Squeeze the hydrometer bulb.
3.2. Submerse the hydrometer tip into the sample.
3.3. Release the bulb, allowing fuel to enter the glass tube until it completely floats the glass bulb inside the tube.
3.4. Gently spin the hydrometer to relieve the surface tension of the fuel sample. Read the scale on the glass bulb at the point where the top of the
fuel sample contacts it. By reading this value, it will give an approximate fuel oil specific gravity. Refer to tool instructions on how to
determine API Gravity.
4. Refer to Fuel Oil Specific Gravity Requirements table. If the correct fuel is being used in the conditions listed in Fuel Quality, and meets number
1-Diesel or number 2-Diesel fuel oil specific gravity requirements, fuel is OK. If not, the fuel should be replaced.