One problem related to timing tensioner has been reported for the 2008 Ford Explorer. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2008 Ford Explorer based on all problems reported for the 2008 Explorer.
The car was traveling at 30 mph from store to school in midday two miles, started ticking and got louder as traveling back home(2 mile). At home popped hood, listened for noise ,engine idling smoothly ,but ticking or rather hitting noise from top of valve cover,drivers side front,was very prevalent. Turned off car and pulled chain tensioner out and looked inside with snake camera and saw broken plastic parts all around timing chain area. I searched online and found this has been happening from 1997 to currant. Plastic, vinyl parts in the motor repeatedly shattering for years, costing consumers thousands in repairs. These v-6 and v-8 Ford motors are flawed because of these weak parts. This is a engineering bomb, and when you least expect it, the timing chain goes bad at 72931. 5k. That should not happen. The motor has to be pulled to change the four chain cassettes, or single cassette,because vinyl parts are in the pan and in the oil galleys. 18-19 hours on book the repairs are expensive, unreasonable,and a cover-up. Ford could change the part, but chooses not to. An addition 3000$ to the cost of ownership is not acceptable in the first five years. That's what the n. H. T. S. A. Is to be observing. The car is inoperable, for fear of having the valves contact the piston, and end up with metal in the bottom of the oil pan. Someone is responsible for the decision to make these parts out the inferior media. P. S. Regular oil changes are documented.