Your engine customer/installer may complain of oil seepage from the rear main bearing seal, but a closer insepection may reveal the cause of the seepage is due to the accumulation of dirt and debris around the outside of the rear main seal on some 1997-2005 4.0L Jeep engines. This condition may occur more frequently if the vehicle is used in off road conditions.
A spacer plate is used to mate the transmission bellhousing to the back of the engine. The spacer plate has a slot machined into it at the 12 o’clock position (Figure 1). A small opening may occur at the spacer slot when the spacer is mounted. The narrow spacer opening at the top of the transmission bellhousing may allow small size debris to enter the bellhousing and accumulate around the outside of the rear main engine seal. If debris accumulation becomes significant, damage to the rear main seal may result (Figure 2).
Repair Procedure:
1. Locate the narrow opening created by the spacer plate. The spacer opening can be viewed when looking towards the rear of the engine and top of the transmission.
2. Thoroughly clean the immediate area around the spacer opening with throttle body cleaner (p/n 04897156AA). Allow cleaner to dry.
3. Apply a sufficient amount of RTV over the spacer opening. Verify that the spacer opening is completely sealed off by the RTV.
Some or all of this information was provided by the Automotive
Parts Remanufacturers Association (APRA). For more information on
technical bulletins available through APRA call 703-968-2772 or visit www.AutoBulletins.com.