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Service bulletin PIT5734

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10172339
Published by NHTSA2020-03-09
Manufacturer's numberPIT5734
Manufacturer's date2020-02-28
NHTSA componentENGINE; VISIBILITY:DEFROSTER/DEFOGGER/HVAC SYSTEM:HEATER CORE

NHTSA's summary

This Preliminary information communicates an issue with poor heater performance and advises dealerships to inspect the heater core inlet and outlet hoses for being twisted or kinked.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Engine, Glass, wipers and mirrors, Heating and air conditioning

Vehicles listed
CHEVROLET SILVERADO 15002020 (the catalog's model; the bulletin names a series or trim of it)
GMC SIERRA 15002020 (the catalog's model; the bulletin names a series or trim of it)

Listing a model year does not mean every vehicle of it is concerned: the document says which.

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