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Service bulletin 08-07-30-033

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 id10026003
Published by NHTSA2008-09-24
Manufacturer's number08-07-30-033
Manufacturer's date2008-07-01
NHTSA componentPOWER TRAIN:AUTOMATIC TRANSMISSION

NHTSA's summary

GMC: TRANSMISSION SLIP, SHUDDER OR GRIND NOISE IN FIRST, SECOND OR REVERSE, DTC P079A SET (REPLACE TRANSMISSION REAR CASE ASSEMBLY). FOR TWO-MODE HYBRIDS WITH 2ML70 AUTOMATIC TRANSMISSION. *PE

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

P079A

Vehicles listed
CHEVROLET TAHOE2008

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
06-00-89-031D2021-09-07. Service bulletin. OEM and Remanufactured Engine and Automatic Transmission/Transaxle Identification
06-00-89-031D2021-04-20. Service bulletin. OEM and Remanufactured Engine and Automatic Transmission/Transaxle Identification
150089004C2021-03-08. Service bulletin. This service bulletin provides technicians with updated information to help identify the differences between what is considered a fluid leak, and what is considered fluid seepage.
1308116001F2020-12-07. Service bulletin. The intent of this technical bulletin is to identify aftermarket ALDL or DLC interface devices as potential sources for causing multiple customer concerns that do not have other diagnostic methods to identify them.
PIT4585F2019-04-08. Service bulletin. This Preliminary Information communication provides information to the technician that the Serial Data Gateway Module (SDGM) may report "Crash Sense Failed" and the 300v Hybrid Battery Contactors will remain open until the Hybrid Powertrain Control Module's (HPCM) High Voltage (HV) DTCs are reset. And How to Reset.
PIP4681E2018-08-20. Service bulletin. This Preliminary Information communication provides information to the technician about vehicles that have a random bump, chuggle, or fishbite sensation when crowding the throttle slightly with the Torque Converter Clutch on while cruising at 35-60 miles per hour. Technician should follow all published Service Information diagnostics if the concern is repaired compare to a like vehicle with the same options.
PIP3366C2018-08-20. Service bulletin. 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's are advised this condition should be deemed a normal characteristic of 4WD low operation.
09-07-30-018D2018-06-04. Service bulletin. This informational bulletin provides a revision for 09-07-30-018C to add the 2014 model year and update the Labor Operation.
01-00-89-010J2018-05-21. Service bulletin. This informational bulletin provides a revision for 01-00-89-010I to add the 2013 model year.
02-07-30-029W2018-05-21. Service bulletin. This informational bulletin provides information to the technician on what parts of an engine or transmission will require the PQC to be notified.