Bonneville V6-231 3.8L (1984)
Clutch: All Technical Service Bulletins
A/T - Slips In Reverse
Number
84-7-30
Date
7/84
Subject:
SLIPS IN REVERSE, (BURNED LO & REVERSE, CLUTCH PLATES) -- 1984 THM 700-R4
WASHER UNDER BOLT LOCATION
If a 1984 Model THM 700-R4 transmission experiences a "slips in reverse" along with burned lo and reverse clutch plates, a possible cause may be an
incorrectly machined boss bolt hole at the end of the line bias valve (Fig. 1). The boss surface may have been machined off about 0.040"-0.050" too
much. This allows the valve body attaching bolt that locates through the sleeve at the end of the line bias valve to interfere with the lo and reverse clutch
plates, preventing them from releasing properly. When this occurs, the bolt end and the clutch plates will have wear or burrs..
SERVICE PROCEDURE:
1.
Remove lo & reverse clutch assembly from transmission.
2.
Check clutch plates for evidence of burrs caused by bolt interference.
3.
If still not sure, install valve body back on transmission and check inside case to determine if bolt protruding is through.
4.
Remove the bolt that is located at the end of the line bias valve.
5.
Install a 2 mm (0.080") washer under bolt head (Fig. 1).
NOTICE:
If the bolt already has a washer, be certain when reassembling the washer that it is in the correct location.
6.
Reassemble, following procedure outlined in the service manual.
NOTICE:
Washer is not required, if above condition does not exist. Adding washer, when not needed, could result in stripping
bolt threads in case.
