| Subject: | Fuel Filter Replacement |
| Models: | 2005 Chevrolet W-Series Medium Duty Tilt Cab |
| 2005 GMC W-Series
Medium Duty Tilt Cab |
| 2005 Isuzu N-Series Commercial Models |
| with Isuzu 4HK1-TC Diesel Engine (RPO IL5) |
Fuel Filter Usage
The 4HK1-TC fuel system is a newly designed high pressure "common rail"
system that is very sensitive to fuel quality and fuel condition. Because of this,
a fuel filter of adequate volume, mesh size and configuration must be used. Use ONLY
a factory original equipment manufacturer (OEM) fuel filter, GM P/N 94369299
(Isuzu P/N 8-94369-299-3), when servicing the fuel filter assembly. Aftermarket
fuel filters do not meet OEM standards and may result in poor engine performance or
damage the fuel system.
Fuel Filter/Water Separator Service Intervals
Replace the fuel filter on the frame rail every 20,800 km (13,000 mi)
or 12 months, whichever comes first, or more frequently, if clogged. Drain water from
the water separator on the frame rail every 10,400 km (6,500 mi) as
stated in the Owner's Manual.
