# P0721 on the 2004 GMC Sierra

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

Nobody has written a description of this code yet.

## Bulletins for this model year that name P0721

- [10014863](https://open.wenmarpro.com/bulletins/10014863), 2005-05-11: NO SHIFT, SPEEDOMETER ERRATIC/INOPERATIVE, P0721 C0237 P0500 C0055. \*TT
- [10005508](https://open.wenmarpro.com/bulletins/10005508), 2004-03-02: ALLISON LCT1000 PRNDL FLASH AND/OR WILL NOT MOVE WITH P0721, P0731, P0732, P0733, P0734, P0743, P0746, P0747, P0776, P0777, P1720, P1721, P1723 AND P1724. \*TT
- [10005451](https://open.wenmarpro.com/bulletins/10005451), 2004-02-27: ALLISON LCT1000 NO SHIFT, SPEEDOMETER ERRATIC/INOPERATIVE, DIAGNOSTIC TROUBLE CODES \(DTCS\) P0721, C0237 POSSIBLE ANTI\-LOCK BRAKE SYSTEM \(ABS\) LAMP ON. SI BULLETIN 1408789. \*TT