Aurora40
Well-known member
[font=Arial, Helvetica, sans-serif] 2005 GM gasoline engines require the use of an engine oil that has the American Petroleum Institute (API) Starburst AND states that it meets GM Standard GM 6094M (non-synthetic) or GM4718M (synthetic). Failure to use the recommended engine oil can result in engine damage not covered by warranty.
Figure 17 is the list of engine oil brands that meet GM Standard GM 6094M and 4718M as of February 4, 2005.This list will be updated and will be in the Techlink Reference Guide available at http://service.gm.com.

From: http://www.gmtechlink.com/images/issues/mar05/TLMar05e.html#f17
Of note is that not all synthetic oils meet GM's "synthetic" service requirement. Only three oils on this list are approved for motors that require synthetic oil.

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