so we have a couple of trucks with the dreaded 6.0/4.5L diesel from ford. both have given fits but nothing major yet. they'll be coming up on the end of their lease this summer. I have accumulate a ton of stress over this because these were the trucks that were bought to replace 2 of our older 7.3s (both 1997 models) fortunately we kept the old ones as backup because they've had to be on the road quite a bit (one of the trucks we've had since AUG 2008 has spent 3 months at the dealer. I've seen these "bullit proof" oil coolers/egr kits and etc available for these trucks but since they're leased I wasn't going to drop the coin for them, we have buy options at the end which was originally my plan, but as much as I hate to waste all the $$$ we've put into these trucks I can't decide to buy them or send them back. opinions? i wanted to lose the payments for a few years but the engine history/track record has me scared. what would you do?