TSB PIT-3665-D — Chevrolet and GMC Service bulletin

PIT-3665-D is a service bulletin on file with NHTSA for 2 Chevrolet and GMC models, 1998–1999 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.

1Document filed
2Vehicles named
2Model years

Vehicles and model years PIT-3665-D names

VehicleModel years
Chevrolet Silverado 1500 1998
GMC Sierra 1500 1998, 1999

Every document filed under PIT-3665-D

Document IDFiledType
PIT-3665-D May 11, 2016 Service bulletin

What PIT-3665-D covers

Brakes & stability — the component vocabulary NHTSA files this communication under.

← All Chevrolet Silverado 1500 TSB years TSB lookup by model

Questions buyers ask

What is TSB PIT-3665-D?

PIT-3665-D is a service bulletin filed with NHTSA by Chevrolet and GMC, covering 2 Chevrolet and GMC models across the 1998–1999 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 PIT-3665-D cover?

NHTSA's file names Chevrolet Silverado 1500 (1998); GMC Sierra 1500 (1998–1999). 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 PIT-3665-D a recall, and is the repair free?

No. PIT-3665-D 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 PIT-3665-D?

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 PIT-3665-D, its date, and NHTSA's own summary from the public file.

Data updated 2026-08-20 from NHTSA's public records

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 PIT-3665-D. Check any specific vehicle's open recalls by VIN at nhtsa.gov/recalls.