Problem Description and Possible Solution
On this V8 engine, timing chain problems are very common. Because the timing chain tensioners were made from plastic, they can fail prematurely and cause serious engine damage. A noticeable engine noise while idling or during a cold start can indicate a timing chain tensioner problem. The engine noise may also be accompanied by a rough or uneven engine idle. Improved components are available to remedy this problem.
Average mileage: 88,924 (6,600–185,890)
Engines affected: 3.0L V6, 4.0L V8
7 people reported this problem
made a strange noise while in park idling shhut motor off for 10 minutes tried to restart and no-go both tensioners broke during start up and chains stretched (I know how does metal stretch?) dealerships will rape and violate your ass, but they have the parts and tools to do the job. good luck.
My engine died one day. No compression on the left bank. The secondary timing chain had broken. One of the shoes of the tensioner had broken and had deep sprocket marks in the plastic. I think the plastic shoe broke first and then jammed between the sprocket and the chain which subsequently broke. Plastics tend to deteriorate in heat by losing their plasticiser and become brittle.