GM Service Manual Online
For 1990-2009 cars only

NOISY OR INOP. SPEEDOMETER POSSIBLE EXH. MANIFOLD CONTACT

NOISY OR INOPERATIVE SPEEDOMETER

VEHICLES AFFECTED: 1985-1987 C/K AND R/V 2, 3 MODELS WITH 4.3L, 5.7L, OR 7.4L CARBURETED ENGINES

Some 1985, 1986, and 1987 C/K and R/V models trucks may experience a noisy or inoperative speedometer. This condition may be caused by the speedometer cable contacting the engine exhaust between the cable connection on the transmission or transfer case and the first cable clamp located on the floor pan. If the contact occurs, the high exhaust temperature may damage the speedometer cable.

A new design speedometer cable has been released to repair this condition when found (See Figure No. 1 for K models, Figure No. 2 for C models). The new cable has a foam collar where it mates with the first clamp, that when clamped, holds the cable in correct alignment and prevents cable droop. The new gray cable is also three inches shorter than the black cable it replaces. Follow the procedure in Section 8C of the Light Duty Truck Service Manual to install the new cable.

Parts Information

Part Number Description Application Quantity ----------- ----------- ----------- -------- 15549223 Cable Assembly K and V 2,3 with 1 4.3L, 5.7L, 7.4L All Transmissions

15549220 Cable Assembly C and R 3 with 4.3L, 1 5.7L, 7.4L with M40 Automatic Transmission


Object Number: 79270  Size: FS


Object Number: 79269  Size: FS

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.