Info - Replacement of Output Flange Nut When Servicing Transmission
| Subject: | Replacement of Output Flange Nut When Servicing Transmission |
| Models: | 1999-2007 Chevrolet W-Series Medium Duty Tilt Cab Models |
| 1999-2007 GMC W-Series Medium Duty Tilt Cab Models |
| 1999-2007 Isuzu NPR/NQR Commercial Models |
| with 4HE1-TC or 4HK1 Diesel Engine and Aisin Automatic Transmission |
This bulletin is being revised to add model years and the 4HK1 engine. Please discard Corporate Bulletin Number 03-07-30-035A (Section 07 -- Transmission/Transaxle).
Recent transmission failure investigation has determined that some replacement transmissions may have failed due to incorrect flange nut torque.
When performing any repairs on an Aisin transmission assembly that requires the removal of the output flange nut (also called coupling driver nut), YOU MUST REPLACE THE OUTPUT FLANGE GASKET (O-RING) AND FLANGE NUT. The technician should install, tighten and stake the output flange nut when replacing. Refer to the steps in the Rear Cover Oil Seal procedure in the Automatic Transmission On-Vehicle Service sub-section of the Isuzu Commercial Truck Service Manual-Chassis.
Notice: Failure to achieve or exceed the correct tightening specification on the output flange nut or reusing the old nut may lead to premature transmission failure.
Make sure that the output flange nut is tightened to the proper specified torque.
Tighten
Tighten the output flange nut to 170 N·m (125 lb ft).
Parts Information
For Chevrolet and GMC Models:
Part Number | Description |
|---|---|
97202082 | Nut, A/T Coupling Driver |
97202087 | Gasket, Coupling Driver |
For Isuzu Models:
Part Number | Description |
|---|---|
8-97202-082-0 | Nut, A/T Coupling Driver |
8-97202-087-0 | Gasket, Coupling Driver |
Parts are to be obtained from AIPDN.
