O.K. Guys - Here's the deal: Just leased a new Jeep Grand Cherokee Special Edition with a 4.0 litre inline 6 today for the young & vivacious Mrs. Harbor. It's sitting in my safe & warm garage now with 36 miles on the odometer. Vehicle has 4WD quadra - trac. Lease is for 2 years / 24K miles, and in almost all cases, one of my in-laws / out-laws ( Dr. Phil, I need you NOW) always buys our vehicles upon lease turn-in. So...I'm looking to break it in correctly and to make sure that whichever Deliverance in-bred relative / neighbor buys it, can get the max engine life out of the vehicle. What are your recommendations for: 1) a good engine break-in procedure, and 2) which oil to use at the recommended 3K mile oil changes? I know that the Jeep inline six has been around forever, is almost bullet- proof,indestructable, ...etc. And, yes Christopher Columbus used them in the Nino, Pinto (no, not Ford Pinto) and Santa Maria with no problems other than the reported occasional piston slap on cold start-up by his crew. My plan is to change the oil at 1K with Castrol 10W-30 (with a shot of Schaeffer's Moly < despite the recent disappointing moly post >) and then every 3K thereafter with either Schaeffer's, Pennzoil or Castrol 10W-30 (Attn: Tim Mills - Any 10W-30 deals out there? ) Filters will probably be Wal-Mart Supertech. 5W-30 may be used in the lovely Michigan winters. Any views, comments or opinions to make sure this puppy goes at least 200K? As always, I appreciate and value the input of this knowlegable group. Thanks!