Chevrolet Trailblazer 2002–2003 — technical service bulletin
Bulletin 00078F · NHTSA communication 10004246 · issued Jan 1, 2004
Technical service bulletin
communication type
Engine and Engine Cooling
component
2002–2003
model years
6
vehicle entries
Official summary
Engine knock noise initial startup in cold ambient 10 degrees centigrade/50 degrees fahrenheit. *tt
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.