I have a 2005 XK8 4.2 which is running perfectly (for the moment!). I assume it is fitted with the all-metal type 3 tensioners. Do these need any specific checking or servicing? Am I likely to need to replace them? The car has just covered 90,000 miles.

 

There has been a couple reports of metal secondary tensioner failures but that is far fewer than the plastic versions. More on the order of what would be expected of any mechanical part. One part of the chain system that is of some concern is the primary slipper arms. They seem to have a life shorter than the total engine but do not cause the total engine failure of the upper tensioners.