TSB PIT3665M — Cadillac, Chevrolet and GMC Service bulletin
PIT3665M is a service bulletin on file with NHTSA for 3 Cadillac, Chevrolet and GMC models, 1998–2001 model years. A TSB is factory repair guidance, not a recall — the repair is not automatically free.
What the bulletin says. This Preliminary Information communication advises the technician that the Hydro-Boost is not serviceable and will need to be replaced if the brake pedal moves or applies on its own at a full turn.
NHTSA's own summary of the document, quoted from the public manufacturer-communications file.
Vehicles and model years PIT3665M names
| Vehicle | Model years |
|---|---|
| Cadillac Escalade | 2001 |
| Chevrolet Silverado 1500 | 1998, 1999 |
| GMC Sierra 1500 | 1998 |
Every document filed under PIT3665M
| Document ID | Filed | Type |
|---|---|---|
| PIT3665M | May 19, 2023 | Service bulletin |
What PIT3665M covers
Electrical — the component vocabulary NHTSA files this communication under.
Questions buyers ask
What is TSB PIT3665M?
PIT3665M is a service bulletin filed with NHTSA by Cadillac, Chevrolet and GMC, covering 3 Cadillac, Chevrolet and GMC models across the 1998–2001 model years. NHTSA's summary reads: This Preliminary Information communication advises the technician that the Hydro-Boost is not serviceable and will need to be replaced if the brake pedal moves or applies on its own at a full turn.
Which vehicles does PIT3665M cover?
NHTSA's file names Cadillac Escalade (2001); Chevrolet Silverado 1500 (1998–1999); GMC Sierra 1500 (1998). A bulletin number can be re-issued against more vehicles later, so check the model-year list on this page against your own.
Is TSB PIT3665M a recall, and is the repair free?
No. PIT3665M is repair guidance the manufacturer sent its dealers, not a safety defect finding. You pay for the work unless the vehicle is still under warranty. Recall repairs, by contrast, are always free.
How do I get the full text of PIT3665M?
Take the document ID to a dealer's service desk, or search NHTSA's manufacturer-communications records. This page carries every document ID filed under PIT3665M, its date, and NHTSA's own summary from the public file.
Every number on this page is a count of records in the federal complaint, recall, and investigation files published by NHTSA's Office of Defects Investigation. This page lists only what NHTSA's manufacturer-communications file records under PIT3665M. Check any specific vehicle's open recalls by VIN at nhtsa.gov/recalls.