TSB 990730016A — Chevrolet and GMC Service bulletin
990730016A is a service bulletin on file with NHTSA for 5 Chevrolet and GMC models, 1990–1996 model years. A TSB is factory repair guidance, not a recall — the repair is not automatically free.
What the bulletin says. DIAGNOSTIC INFORMATION FOR INTERMITTENT TRANSMISSION DOWNSHIFT, SLIP, BUSY/CYCLING TCC OR NOISY COOLING FAN.
NHTSA's own summary of the document, quoted from the public manufacturer-communications file.
Vehicles and model years 990730016A names
| Vehicle | Model years |
|---|---|
| Chevrolet Blazer | 1990, 1991, 1992, 1993, 1994, 1995 |
| Chevrolet S10 | 1990, 1991, 1992, 1993, 1994, 1995, 1996 |
| Chevrolet Silverado 1500 | 1990, 1991, 1992, 1993, 1994, 1995, 1996 |
| Chevrolet Suburban | 1990, 1991, 1992, 1993, 1994 |
| GMC Sierra 1500 | 1990, 1991, 1992, 1993, 1994, 1995, 1996 |
Every document filed under 990730016A
| Document ID | Filed | Type |
|---|---|---|
| 990730016A | October 1, 2002 | Service bulletin |
What 990730016A covers
Transmission & drivetrain — the component vocabulary NHTSA files this communication under.
Questions buyers ask
What is TSB 990730016A?
990730016A is a service bulletin filed with NHTSA by Chevrolet and GMC, covering 5 Chevrolet and GMC models across the 1990–1996 model years. NHTSA's summary reads: DIAGNOSTIC INFORMATION FOR INTERMITTENT TRANSMISSION DOWNSHIFT, SLIP, BUSY/CYCLING TCC OR NOISY COOLING FAN.
Which vehicles does 990730016A cover?
NHTSA's file names Chevrolet Blazer (1990–1995); Chevrolet S10 (1990–1996); Chevrolet Silverado 1500 (1990–1996); Chevrolet Suburban (1990–1994); GMC Sierra 1500 (1990–1996). 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 990730016A a recall, and is the repair free?
No. 990730016A 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 990730016A?
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 990730016A, 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 990730016A. Check any specific vehicle's open recalls by VIN at nhtsa.gov/recalls.