Important: Use compressed natural gas (CNG) that meets the specifications of SAE
J1616. These specifications place limits on particulate contamination and
moisture content. CNG that meets these specifications provides improved
driveability and emission control system performance. CNG that does not
meet these specifications may cause fuel system or engine damage. If your
GM dealer determines that the cause of the condition is the type of CNG
used, repairs may not be covered under warranty.
This schedule information is supplemental to the gasoline service manual
information. Refer to the C/K Pickup Service Manual for additional
maintenance items.
The services shown in this schedule up to 193,000 km (120,000 miles)
should be performed after 193,000 km (120,000 miles) at
the same intervals.
Every 12 500 km (7,500 Miles)
| • | Inspect the CNG fuel lines and the fittings for leaks. |
| • | Inspect the CNG fill valve O-ring. |
| • | Inspect the CNG fill valve filter. |
Every 24 000 km (15,000 Miles)
Drain the fluids from the in-line CNG filter housing.
Every 100 000 km (60,000 Miles)
| • | Remove and clean the CNG fill valve filter. |
| • | Replace the spark plugs. |
| • | Inspect the spark plug wires. |
| • | Replace the in-line CNG filter. |
Every 200 000 km (120,000 Miles)
Replace the high pressure regulator (HPR) filter.
