Grand Prix V6-231 3.8L (1983)
Clutch: Customer Interest
A/T - Slipping During 1-2 or 3-4, No 1-2 or 3-4 Upshift
Number 83-T-27
Section 7 Date 04/83
Subject:
DIAGNOSIS PROCEDURE FOR BURNED 2-4 BAND AND/OR 3-4 CLUTCH - THM 700-R4
The following diagnosis procedure is for a burned 2-4 band and/or a burned 3-4 clutch. The probable customer comment for these conditions would be:
1) slipping 1-2 shift or no 1-2 shift; and/or, 2) slipping 2-3, shift or no 2-3 shift. This procedure is a general guide and you will need to refer to your
Service Manual for additional information if questions arise.
SERVICE PROCEDURE
1.
Verify the condition as follows:
a.
Check and correct the oil level.
b.
Check the T.V. cable for sticking or binding. Adjust the T.V. cable.
c.
Road test the vehicle at normal operating temperature and check oil pressure.
2.
For conditions of high or low oil pressure, refer to the Service Manual for proper diagnosis.
3.
As a diagnosis aid, you can check the oil pressure differential between line pressure and the second, third, or fourth clutch. If the pressure
differential between line and any of these clutch circuits is more than 10 psi (assuming your oil pressure gages are accurate) there is a possible oil
leak in that clutch oil circuit.
1.
DIAGNOSIS PROCEDURE FOR A SLIPPING 1-2 OR NO 1-2 SHIFT
1.
After verifying the condition, remove and disassemble the 2-4 servo cover and piston assembly. Check the following:
a.
Proper servo pin length.
b.
Damaged or worn seals. Replace if necessary.
c.
Porosity, nicks, burrs, sharp edges, or ring groove damage in the pistons, cover, servo pin, or servo bore.
Figure 1
d.
Blocked servo exhaust hole (see Figure 1 on the following page).
e.
Blocked or missing orifice cup plug in the case servo bore.
2.
Reassemble and install the 2-4 servo piston and cover.
3.
Remove and inspect the governor assembly and cover:
a.
Governor Assembly - Damaged gear teeth, scored sleeve, stuck or sticking valve, missing springs, and sticking or damaged weights.
b.
Case Governor Bore - Scoring, damage, or governor support pin off location, loose, or missing.
