A/T - 4L80-E/4L80-EHD Grunt or Squawk Noise
91chevy25
GMC NUMBER: 91-7A-135
GROUP: 7A Automatic Transmission
DATE: August, 1991
CORPORATE NUMBER: 177117
SUBJECT: GRUNT OR SQUAWK NOISE (LUBRICATED YOKE SLEEVE TO AXLE SHAFT) 4L80-E NEW SERVICE PACKAGE
MODELS: 1991 C1 TRUCKS WITH 4L80-E AND 7.4L ENGINE AND G313 VAN WITH 4L80-E/4L80-EHD
Figure 1:
Some HYDRA-MATIC 4L80-E/4L80-EHD transmissions may experience a grunt or squawk noise coming from the output shaft area. This noise is caused by the propshaft moving back and forth on a non-lubricated transmission output shaft. A new Output Shaft Assembly was released which adds a greased sleeve to lubricate the yoke to output shaft area and dampens the noise. A new propshaft shaft assembly was released which has grease added to slip yoke splines, a vented welsh plug and slight increase in length. New Models, which feature this grease sleeve, were released to replace current models:
Previous Models New Models
AJP ADP
BRP BBP
CSP CBP
HSP DDP
HTP DSP
Date of Production Change: (See Figure 1)
Starting May 13, 1991 (Julian Date 133), all HYDRA-MATIC 4L80-E/4L80-EHD AJP, BRP, CSP, HSP, and HTP models were built with the new Greased Sleeve.
Service Parts Information:
Part
Number Part Description
8683922 Package, Sleeve and Seal Assembly
Output
*8661596 Shaft and Bushing Assembly-Output
15679617 Propshaft (model C1 with L19)
15679625 Propshaft (model G31305/6 with LB4/
L05/LL4 and MT1
Model G31303-32 with L05/LL4 and
C6P)
15679626 Propshaft (model G31305/6 with L19
model G31303-32 with C6P and L19
model G31303-32 with C6S/C7A/C7Q)
112345879 Lubricant, Special
* If the output shaft journal is not finished (ie. built before November 12, 1990 {Julian Date 316}), then a new Output Shaft Assembly must be installed. Transmission must be removed from vehicle in order to replace Output Shaft Assembly with machined journal. Parts are expected to be available on 8/19/91. Until then, normal part orders will not be accepted by GMSPO. In an emergency, contact your division service department for the required parts order authorization.
Figure 2:
Figure 3:
Figure 4:
On-Vehicle Service Procedure: (See Figures 2, 3, and 4)
The output shaft journal must be machine finished in order to install the new sleeve. (See Figure 4)
1. Remove propshaft from transmission output shaft.
2. Remove transmission extension assembly.
3. Install the new service package onto output shaft journal.
4. Lightly coat splines of transmission output shaft with grease (P/N 12345879) to completely cover the entire spline.
5. Reinstall extension assembly.
6. Apply grease (P/N 12345879) to slip yoke of new propshaft with brush or swab, so as to completely cover the entire spline with a light coating of grease.
7. Reconnect new propshaft.
Service Manual Reference:
Refer to the Unit Repair Service Manual Section 7 for proper replacement procedures for Output Shaft Assembly and appropriate service manual section for propshaft replacement.