| Subject: | Engine Crankcase Flush |
| Models: | 2003 and Prior GM Cars and Trucks |
| 2003 and Prior Isuzu Light and Medium Duty Trucks |
General Motors is aware that some companies are marketing tools and
equipment to support engine crankcase flush procedures. GM does NOT endorse
or recommend crankcase flushing for any of its gasoline engines. Analysis
of some of the materials used for crankcase flushing procedures indicate incompatibility
with GM engine components and the potential for damage to some engine seals
and bearings. Damage to engine components resulting from crankcase flushing
procedures is not covered under the terms of the New Vehicle Warranty.
