I can relate!!
The Achille's heel in our case was a catastrophic coolant leak. This has happened to me, on my 2006 LR3, with 194K miles. We were driving, not too far from home and had the alert: "Reduced Engine Performance". Little did we know (no warning lights or gauges, due to engineering/placement of heat sensors), that we had a massive loss of coolant from the plastic reservoir. This causes head gasket failure, and you can imagine the rest. These engines (4.4L; 5.0L are even worse!) die quickly from over-heating! From what I'm told by the techs, there is no work-around to overcome the engineering flaw. Bottom line: check your engine frequently for leaks, faulty hoses, etc.. And, if you see the warning light: "Reduced Engine Performance", pull over immediately, and shut down the engine; hopefully, fast enough to save the engine!