K 3500 Truck 4WD V8-379 6.2L DSL VIN C FI (1992)
Oil Filter Adapter: All Technical Service Bulletins
Oil Filter Adapter - Oil Leakage
File in Section: 6 - Engine
Bulletin No.: 57-61-33
Date: November, 1995
Subject:
Oil Leaking at Oil Filter Adapter (Replace with a New Design Adapter)
Models:
1988-94 Chevrolet and GMC Truck K Models (Four-Wheel Drive) with 6.2L or 6.5L Diesel Engines (VINs C, J, F, P, S - RPOs LH6, LL4, L65, L49,
L56)
Condition
Some vehicles may experience an oil leak at the oil filter adapter. The leak may occur at either the interface between the adapter and engine block or at
the copper washer, bolt, and adapter housing. Replacement of the copper washer does not permanently repair the oil leak.
Cause
An early design (View A) uses a multiple piece adapter assembly with an oil filter (1), connector (2), adapter seal (3), adapter housing (4), pipe plug (5),
adapter 0-ring seals (6), copper washer (7), and bolt (8). The copper washer (7) yields over time causing loss of bolt torque that results in the oil leaks.
Correction
A new design (View B) consisting of an oil filter (1) and an adapter housing assembly (4) was released during the 1994 model year. The new design
(View B) is an assembly including the attaching bolt and does not use a copper washer.
1.
Check for early design oil filter adapter. Identify the early design (View A) by a pipe plug (5) in the adapter housing (4).
2.
Inspect and confirm the oil leak is at the oil filter adapter area.
3.
Remove the early design oil filter adapter by removing the bolt (8).
