[JarvisTurkenton]

Couldn’t upload video, my shop is being very aggressive about replacing timing chain on 2015 F25… do the photos do that justice?

[bmwPower99]

The lower oil chain has a slack measurement and the other chains are tested based on tensioner extension. But you can't check.any of that easily.

[JarvisTurkenton]

I guess the pictures don’t do it justice as the video shows more play… either way, best to err on caution, 94k miles never been replaced.

[gav1ndica]

Changed mine at 97k, chain slack was equal to that in the video.

[Opie55]

You need to remember that there is a hydraulic tensioner the works on oil pressure. So the issue is not just slack, but slack when. If my engine has been off for several hours and the pressure has bled off the tensioner, it has slack like your photo. If I start the engine and let it run a few minutes, then shut if off and check again, there is no slack at all.

[BMWvsEverybody]

I check my (N20 F25) chain slack every so often. I have never experienced that much at any time. Cold or warmed up. It's always tight.

[Wayfastwhitey]

Is this a wear item, like brake pads, or does replacement once fix the issue?

[Wgosma]

Originally Posted by Wayfastwhitey

Is this a wear item, like brake pads, or does replacement once fix the issue?

No, in general BMW has used chains on virtually all their engines since the 1990’s; it would be considered a lifetime component.
The N20 4 cyl engine prior to 2016 had problems with the plastic chain guides breaking into pieces, I don’t think those engines had chain issues to best of my knowledge.

[Wayfastwhitey]

Originally Posted by Wgosma

No, in general BMW has used chains on virtually all their engines since the 1990’s; it would be considered a lifetime component.
The N20 4 cyl engine prior to 2016 had problems with the plastic chain guides breaking into pieces, I don’t think those engines had chain issues to best of my knowledge.

Ok, the chain was replaced on my 2014 ~60k mark. At 113k now. Was wondering if I should do it again.

[Brandoch]

Originally Posted by Wayfastwhitey

Ok, the chain was replaced on my 2014 ~60k mark. At 113k now. Was wondering if I should do it again.

Maybe do some research, the timing chain guide issue is very well documented at this point. Lots of post, class action lawsuits, and BMW documents. You keep asking the same question over and over.

[Wayfastwhitey]

Originally Posted by Brandoch

Maybe do some research, the timing chain guide issue is very well documented at this point. Lots of post, class action lawsuits, and BMW documents. You keep asking the same question over and over.

Of course, I read everywhere over and over there’s issues and it needs to be replaced, and yet not one instance has anyone said the fox is one and done. Normally there’s a problem and you can fix it. But if the design is garbage then it’s not really fixed…