Firebird V8-305 5.0L (1982)
Governor Pressure Switch: All Technical Service Bulletins
A/T - Erratic or No Upshift (Governor Drive Gear)
Bulletin Number:
88-7-20A
Reference Number:
877123R
Publish Date:
4/88
Subject:
ERRATIC OR NO UPSHIFT (NEW GOVERNOR DRIVEN GEAR)
Models
Affected:
1982-1988 VEHICLES EQUIPPED WITH THM 700 R4 (MD8) AUTO TRANS
This bulletin is being revised to include Labor Op and labor time. Please discard bulletin 88-7-20 issued 3/88.
FIGURE 1 - "APPLECORED" GOVERNOR DRIVEN GEAR
BULLETIN COVERS:
A THM 700-R4 transmission with an erratic or no upshift condition may be due to applecoring of the governor driven gear.. "Applecoring" of the
governor driven gear (refer to Figure 1) may be caused by nicks and/or burrs on the governor drive gear. The new governor driven gear has a higher
fiberglass content. Also, inspect the output shaft for nicks and/or burrs on the governor drive gear. Replace the output shaft if nicks and/or burrs are
found.
FIGURE 2 - THM 700-R4 TRANSMISSION IDENTIFICATION INFORMATION
DATE OF PRODUCTION CHANGE:
(Figure 2)
Beginning July 06, 1987 (Julian Date 187) all THM 700-R4 transmissions were produced with the new governor driven gear.
SERVICE ACTION:
When servicing any THM 700-R4 governor driven gear for an "applecored" condition, use the new governor driven gear and pin package listed under
"Service Parts Information". NOTE: The new THM 700-R4 governor gear is green in color (the previous gear was blue). This can be used as another
method of identification.
When servicing any 1982 through 1986 THM 700-R4 governor driven gear for conditions other than applecoring, the previous governor driven gear,
package number 8642928, should be used until current service stock depleted.
SERVICE PARTS INFORMATION:
