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Service bulletin 667103A

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 id52584
Published by NHTSA1999-12-20
Manufacturer's number667103A
Manufacturer's date1997-03-01
NHTSA componentPOWER TRAIN:AUTOMATIC TRANSMISSION

NHTSA's summary

AUTOMATIC TRANSMISSION 1-2 AND/OR 2-3 UPSHIFT SLIP/FLARE, NO 3RD OR 4TH GEAR, DTC P1870, LAUNCH SHUDDER (REVISE VCM WIRING). *AK

The document

No address for NHTSA's copy can be built for this communication. Ask the dealer for it by the manufacturer's number.

Components

Transmission and driveline, Automatic transmission

Trouble codes named

P1870

Vehicles listed
CHEVROLET C SERIES1996
CHEVROLET G SERIES1996
CHEVROLET K SERIES1996
CHEVROLET L SERIES1996
CHEVROLET M SERIES1996
CHEVROLET P31996
CHEVROLET S SERIES1996
CHEVROLET T SERIES1996
FORD L SERIES1996
GMC C SERIES1996
GMC G SERIES1996
GMC K SERIES1996
GMC M SERIES1996
GMC P31996
GMC S SERIES1996
GMC T SERIES1996
OLDSMOBILE BRAVADA1996

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

Other bulletins for the same vehicles and component
020730024A2002-10-11. Service bulletin. DIAGNOSIS OF CRACKED OR BROKEN TRANSMISSION CASE. *TT 2006 AND PRIOR CARS AND LIGHT DUTY TRUCKS. *TT
010730023B2002-10-09. Service bulletin. SOME CUSTOMERS MAY COMMENT ON A HARSH 1-2 UPSHIFT AND THE CHECK ENGINE LIGHT OR SERVICE ENGINE SOON INDICATOR IS ILLUMINATED AND DIAGNOSTIC TROUBLE CODE P1870 SET. *TT
010730023A2002-02-25. Service bulletin. INFORMATION REGARDING HARSH 1-2 UPSHIFT, SERVICE ENGINE SOON, MALFUNCTION INDICATOR LAMP, OR CEL ILLUMINATED, DIAGNOSTIC TROUBLE CODE P1870 SET. (1996-2000 CHEVROLET AND GMC LIGHT DUTY TRUCK MODELS) *YH
0107300232001-10-24. Service bulletin. SOME OWNERS WITH VEHICLES BUILT BEFORE JANUARY 15,1999 MAY COMMENT ON A HARSH 1-2 UPSHIFT AND MAY ALSO HAVE A CHECK ENGINE LIGHT. *ET
0107300212001-06-26. Service bulletin. THIS TECHNICAL SERVICE BULLETIN STATES THAT TECHNICIANS MAY EXPERIENCE DIFFICULTY IN REMOVING THE CONNECTORS FROM THE PARK / NEUTRAL POSITION SWITCH, USUALLY WHEN TRYING TO REMOVE THE SWITCH DURING TRANSMISSION SERVICE. *TT
0007300262001-04-03. Service bulletin. VEHICLES MAY EXPERIENCE AUTOMATIC TRANSMISSION 1-2 AND 2-3 UPSHIFT SLIP / FLARE NO 3RD OR 4TH GEAR LAUNCH SHUDDER. *JB
8671172000-12-27. Service bulletin. BRIEF INFORMATION REGARDING RUSTY TRANSMISSION FLUID LEVEL INDICATOR. *TT
837110A2000-04-05. Service bulletin. PARK/NEUTRAL POSITION SWITCH CONNECTOR CANNOT BE REMOVED. YD
990730004A2000-01-14. Service bulletin. A CONDITION WITH A RUSTY TRANSMISSION FLUID LEVEL INDICATOR / TRANSMISSION OIL FILLER TUBE. *TT
577126A1999-12-21. Service bulletin. TRANSMISSION FLUID LEAK FROM PUMP BODY (REPLACE BUSHING). *TW