M/T - 3RD Gear Hop-Out on Acceleration or Deceleration

88chevy06

GMC NUMBER: 86-T-156

GROUP: 7B - Manual Transmission


DATE: March, 1988

CORPORATE
NUMBER: 677202R

SUBJECT: 3RD GEAR HOP-OUT (LABELED 2ND GEAR ON THE GEAR SHIFT KNOB)

MODELS: 1985-86 C/K, R/V, P MODELS WITH HM 117 (RPO M20) OR CH/SM 465 (RPO MC8) MANUAL TRANSMISSION

BULLETIN COVERS

Above vehicles may exhibit 3rd gear hop-out on acceleration or deceleration.

DATE OF PRODUCTION CHANGE

December 15, 1987 (Julian Date T15)

SERVICE ACTION

If 3rd gear hop-out occurs, it can be repaired by installing the service part package listed below.

SERVICE PARTS INFORMATION

P/N 8672944 Service Part Package contents:

Quantity Part Description
1 3rd Speed Gear
1 3rd-4th Synchronizer Hub
1 3rd-4th Speed Synchronizer Sleeve
2 3rd and 4th Speed Blocker Rings
3 Synchronizer Keys
2 Synchronizer Springs

SERVICE NOTE

Refill the transmission with only SAE 80W-90 gear lubricant. Do not use automatic transmission fluid or engine oil, which can cause foaming out the vent and durability concerns.

SERVICE MANUAL REFERENCE

Refer to the Unit-Repair Section of the appropriate Service Manual for service procedures.

LABOR OPERATION:

K2700 Transmission Assembly - R & R Transmission, recondition mainshaft.

1988 1985-86 1987-88 1985-88
C K C K R C P

2.8 3.5 3.6 4.1 3.6 4.1 3.6

FIGURE 1:

FIGURE NO. 1 - HM-117 TRANSMISSION IDENTIFICATION INFORMATION CH/SM 465 RPO M20 - MC8