Audi A4 1997–2004 — technical service bulletin
Bulletin 0604 · NHTSA communication 10020721 · issued Apr 7, 2006
Technical service bulletin
communication type
Engine and Engine Cooling
component
1997–2004
model years
12
vehicle entries
Official summary
Oil sludge limited warranty extension. *kb
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.