# Service bulletin 990421004

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.

- Type: Service bulletin
- NHTSA id: 607694
- Published by NHTSA: 1999\-10\-05
- Manufacturer's number: 990421004
- Manufacturer's date: 1999\-08\-01
- Replaces: 867403
- NHTSA component: POWER TRAIN:DRIVELINE:DIFFERENTIAL UNIT; POWER TRAIN:AUTOMATIC TRANSMISSION:LEVER AND LINKAGE:COLUMN SHIFT

## NHTSA's summary

SOME PICKUPS AND FULL\-SIZE UTILITY MODELS WITH AN AUTOMATIC TRANSFER CASE MAY EXHIBIT A BUMP / CLUNK UPON ACCELERATION. \*TT

## 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, Differential

## Vehicles listed

- 1999 to 2000 CADILLAC ESCALADE
- 1998 to 2000 CHEVROLET K1
- 1998 to 2000 CHEVROLET K2
- 1998 to 2000 GMC K1
- 1998 to 2000 GMC K2

## Other bulletins for the same vehicles and component

- [PIP3366C](/bulletins/10143757.md), 2018-08-20, Service bulletin: POWER TRAIN:TRANSFER CASE \(4\-WHEEL DRIVE\); POWER TRAIN:AUTOMATIC TRANSMISSION. This Preliminary information communicates to the dealer technician thatLight Duty Trucks equipped with automatic transmissions and 4 wheel drive may exhibit a condition of grinding/ratcheting type noise when shifting the automatic transmission into park while the transfer case is in 4 wheel drive low \(4LO\) range. Dealers technician\&\#39;s are advised this condition should be deemed a normal characteristic of 4WD low operation.
- [PIP5346](/bulletins/10115081.md), 2017-08-15, Service bulletin: EQUIPMENT; POWER TRAIN:AUTOMATIC TRANSMISSION:COOLING UNIT AND LINES; POWER TRAIN. This Preliminary Information communication provides information to the technician about cooler line fittings that come with the 4T65E General Motors remanufactured transmission may not be the same as Original equipment manufacturer quick connect verses inverted flare. Dealer will need to contact General Motors Technical Assistance Center for further assistance.
- [PIT\-4722](/bulletins/10026804.md), 2008-12-18, Service bulletin: POWER TRAIN:AUTOMATIC TRANSMISSION:COOLING UNIT AND LINES. GMC: FLUID LEAK FROM TRANSMISSION OIL COOLER LINES DUE TO CORROSION. ALL 2000\-2006 LIGHT DUTY TRUCKS EQUIPPED WITH THE LIGHT DUTY AUTOMATIC TRANSMISSION. \*PE
- [PIP4054A](/bulletins/10024345.md), 2008-04-07, Service bulletin: SUSPENSION:REAR; POWER TRAIN:DRIVELINE:DIFFERENTIAL UNIT. EATON LOCKING DIFFERENTIAL CHATTER SHUDDER NOISE ON TURNS, EQUIPPED WITH A LOCKING REAR DIFFERENTIAL RPO G80. \*NJ UPDATED 7/17/2008. \*PE
- [010730038B](/bulletins/10005162.md), 2004-02-10, Service bulletin: POWER TRAIN:AUTOMATIC TRANSMISSION. THE SERVICE ENGINE SOON LAMP IS ILLUMINATED, NO 3RD AND 4TH GEAR, THE TRANSMISSION DOES NOT SHIFT CORRECTLY, THE TRANSMISSION FEELS LIKE IT SHIFTS TO NEUTRAL OR A LOSS OF DRIVE OCCURS. \*TT
- [020730024A](/bulletins/634999.md), 2002-10-11, Service bulletin: POWER TRAIN:AUTOMATIC TRANSMISSION:LEVER AND LINKAGE:COLUMN SHIFT. DIAGNOSIS OF CRACKED OR BROKEN TRANSMISSION CASE. \*TT 2006 AND PRIOR CARS AND LIGHT DUTY TRUCKS. \*TT
- [010730023B](/bulletins/634815.md), 2002-10-09, Service bulletin: POWER TRAIN:AUTOMATIC TRANSMISSION. 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
- [010730038](/bulletins/628934.md), 2002-03-25, Service bulletin: POWER TRAIN:AUTOMATIC TRANSMISSION. SOME CUSTOMERS MAY COMMENT THAT THE SERVICE ENGINE SOON LAMP IS ILLUMINATED, NO 3RD AND 4TH GEAR, THE TRANSMISSION DOES NOT SHIFT CORRECTLY, THE TRANSMISSION FEELS LIKE IT SHIFTS TO NEUTRAL OR A LOSS OF DRIVE OCCURS. \*TT
- [010730023A](/bulletins/627839.md), 2002-02-25, Service bulletin: POWER TRAIN:AUTOMATIC TRANSMISSION. 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
- [010730023](/bulletins/622930.md), 2001-10-24, Service bulletin: POWER TRAIN:AUTOMATIC TRANSMISSION. 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

JSON: [/v1/bulletins/607694](/v1/bulletins/607694)

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