Some models may experience harsh or erratic shifts that are equipped with the THM 700-R4 transmission and 6.2L diesel engine. This condition may be due to a possible interference between the detent rod running underneath the intake manifold and #1-3 or #5-7 injection line clips.
The interference area may be difficult to notice and will require a small swivel mirror to view.
If there is an interference condition, refer to Figure No. 1 for proper injection line clip positioning. Removal of the intake manifold to correct the clip interference will be necessary to correct any interference that exists.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.