Hi Guys, I have been looking at preventive maintenance on my 2011 Navara automatic which has done 170,000 klm and in particular the timing chain. After much reading and discussing it with mechanics, this is what I have found.
1. the wear on the timing chain can be measured electronically by an oscilloscope and it is a simple and quick job. YD25 will do the test for free. YD25 have all the details of how to do it so you can get a tech guy to check it out if you don't get to YD25. I am having mine checked this week.
2. The truck workshop where my vehicles are serviced said they have never replaced a chain on an automatic Navara and they have serviced autos with 350,000 klms on them. That the timing chain problem is caused by the dual mass flywheel oscillating when the motor is idling whipping the tension back and forth on the chain and eventually causing premature failure. I saw a video on the problem where it sounded like the engine was running on 3 cylinders at idle but after diagnosis, they found the flywheel was the problem. It was oscillating so badly it was hitting the edge of the bell housing.
3. The local dealer quoted me $3,000 to $5,000 depending on the parts needed if I wanted to change the chain. YD 25 said it should cost between $2-2,500 for the standard chain and $2,500 to $3,000 for the double-row chain.