3.8L Engine Oil Seepage Due To Front Timing Cover Surface Porosity

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NUMBER: 09-008-07
GROUP: Engine
DATE: November 07, 2007

SUBJECT:

3.8L Engine Oil Seepage Due To Front Timing Cover Surface Porosity

OVERVIEW:

This bulletin involves the replacement of the 3.8L engine timing cover.

MODELS:

2007 – 2008

(JK)

Wrangler

NOTE: This bulletin applies to Wrangler vehicles equipped with a 3.8L engine (sales code EGT) and built on or before September 19, 2007 (MDH 0919XX).

SYMPTOM/CONDITION:

The customer may experience oil seepage from the engine. The oil seepage may be due to surface porosity in the aluminum material used to make the engine timing cover. This surface porosity is located on the surface that mates to the engine block.

The source of the oil seepage may be misdiagnosed. The following are areas where the engine oil seepage may be noticed due to the timing cover porosity:

a). Timing Cover – The seepage may appear as a gasket leak between the cover and the engine block.

b). Oil Filter- The timing cover porosity may lead to an oil seepage at the oil filter or immediate area of the oil filter. The technician may believe that the oil filter is at fault. c). Unused Oil Filter Adapter Boss – Oil may seep along an unused open oil galley and display at the face of the unused oil filter adapter boss. The adapter boss is on the lower left side of the engine.

d). Oil Pan – The technician may believe that the oil pan gasket is at fault.

e). Rear Seal Carrier – The oil may seep along an unused open oil galley and display in the area of the rear crankshaft seal carrier. The technician may believe that the rear crankshaft seal is at fault.

f). Front Crankshaft Seal – The porosity in the timing cover above or around the front crankshaft seal may cause the technician to believe that the front crankshaft seal is at fault.

DIAGNOSIS:

If the above condition is present perform the Repair Procedure.

PARTS REQUIRED:

Qty.	Part No.	Description
1	68003438AA	Cover Kit, Engine Timing (includes: cover and gaskets).
1	04105409AC Mopar 04105409AC FILTER ENGINE OIL Mopar OEM part that fits your specific vehicle FILTER ENGINE OIL Part Number: 04105409AC Manufactured to meet specifications for fit, form, and function Buy on Amazon Price incl. tax, excl. shipping Last update on 2026-06-17 / Affiliate links / Images from Amazon Product Advertising API	Filter, Mopar Engine Oil
6	04761872AC	Oil, Mopar Engine (5W-20 / quart)

REPAIR PROCEDURE:

Replace the engine timing cover. Refer TechCONNECT for detailed Service Information. From the “Service Info” tab select: 9 – Engine 3.8L > Valve Timing > Cover – Timing Chain > Removal and Installation.

POLICY:

Reimbursable within the provisions of the warranty.

TIME ALLOWANCE:

Labor Operation No:		Description	Amount
09-10-15-90		Cover, Engine Timing – Replace (B)	2.8 Hrs.

FAILURE CODE:

ZZ	Service Action

09-008-07

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