Some vehicles equipped with 5.0L and 5.7L V8's and engine oil coolers (RPO KC4) may encounter a "no engine oil pressure" after an oil change or hot soak. This condition may be caused by trapped air in the oil cooler assembly.
Performing the following steps should eliminate any additional occurrences:
1. Remove the engine oil filter.
2. Remove the cooler lines from the cooler adapter assembly.
3. Remove the two (2) cooler adapter to engine block attaching bolts.
4. Drill two (2) 1.6mm (1/16 in.) air bleed holes in the cooler adapter as shown in the attached graphics.
5. Clean adapter with a suitable solvent making sure all metal chips are removed.
6. Reinstall the adapter and torque the attaching bolts to 9 N.m (80 in. lbs.).
7. Reinstall the cooler lines and oil filter.
8. Start engine and check for oil leaks.
Labor Operation Number: T1111
Labor Time : .6 hours
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.