Yes 8mm. 6.35 is wider with more link pieces.

 

Here is another comparison photo of the two chain types. 8mm is top one. Personally I think the 6.35mm setup is much higher quality and probably replaced because of cost-cutting rather than unreliability.

 

So, does the type of chain that is installed say anything about the guides and tensioners that are installed? For example, does having an 8 mm chain mean that the guides and tensioners should be okay, or is there no such relationship?

Thanks

 

The early 8mm moveable aluminium guides had a problem with the steel tensioner pushing directly on the aluminium which eventually wore through. The later guides had a steel insert which the tensioner pushed on, curing that problem. The 6.35mm moveable guides that I just removed from my engine had a plastic insert for the tensioner to push on which showed very little wear after 100K. The fixed plastic guides in my engine showed some signs of cracking so will be replaced. The basic difference I can see between the 8mm guides and the 6.35mm guides is that the channel for the chain to run in is a different width.

 

Thanks for all this info ... which raises a few more questions for me. How would one know if their engine had the earlier or later 8 mm moveable guides? Is there engine number information available for this? I suspect your answer will be to open the engine and have a look but there must be an engine number after which owners can feel assured that they don’t need to do that.

thank you

 

wondering this too.

With a 3.0 2013 build (build date 6-2013) Hoping i got the better guides - if the 3.0 was ever at risk

 

I haven't yet found a way of identifying this. There must be a date after which they started using the new guides and tensioners which can translate to VIN etc, but I don't think this information is necessarily public.

 

Luck of the draw I guess

 

I took a 2012 Range Rover 5.0 engine apart and the guides were the later type so I am guessing that you 2013 is OK.

 

I took a 2012 Range Rover 5.0 engine apart and the guides were the later type so I am guessing that you 2013 is OK.

 

With the Range Rover engines there are VIN ranges avaialble in the TSB - LTB00474NAS3.

No, I don't know why they didn't include Jaguar engines (and VINs) in this TSB either. They share (fundamentally) the same engine and same timing guide flaw.

I tried engaging with a law firm who were bringing a class action suit (based largely on this TSB) against JLR to let them know that it also affected Jaguars of the same period and I had photos of internal engine damage caused by the loose timing chains etc, but they didn't seem interested so I dropped it.

 

Because the left hand doesn't talk to the right hand

 

That's good news

i wonder if there is a way correlate the build date of the Land Rover, with Jaguar to get build date to estimate when the switchover happened