Chevrolet Silverado 2003–2004 — technical service bulletin
Bulletin 01330 · NHTSA communication 10007606 · issued Jan 1, 2004
Technical service bulletin
communication type
Power Train
component
2003–2004
model years
4
vehicle entries
Official summary
Allison lct1000 buzz, moan noise at 1400 rpm with the 8.1 l18 gas engine. *tt
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.