Timing chain replacement

[Diff]

Researching buying a 2012 hybrid up to 200,000 kms.  I have read that timing chains are for life and other reads indicating the chains should be done at 70, 000 miles on the 3.5 engine.  We were looking at the 5.0 L Range Rover engines and all of them should get chains before failure and the BMW  X6 has chains that don’t just wear but actually break  from 26,000 miles onward.  These repairs seem to be over 5-10k euros if everything is done when  in there.  Is this also true for the 3.5 in the Rx 450h which we are really considering to replace our nearly solid 2008 Range Rover 4.2 with 270kms.  Thanks for your perceptions.  Hoping to drive 100,000km  without having to do the chains and vvt  parts.

 

 

 

 

 

 

[Barry14UK]

9 hours ago, Diff said:

Researching buying a 2012 hybrid up to 200,000 kms.  I have read that timing chains are for life and other reads indicating the chains should be done at 70, 000 miles on the 3.5 engine.  We were looking at the 5.0 L Range Rover engines and all of them should get chains before failure and the BMW  X6 has chains that don’t just wear but actually break  from 26,000 miles onward.  These repairs seem to be over 5-10k euros if everything is done when  in there.  Is this also true for the 3.5 in the Rx 450h which we are really considering to replace our nearly solid 2008 Range Rover 4.2 with 270kms.  Thanks for your perceptions.  Hoping to drive 100,000km  without having to do the chains and vvt  parts.

Would be interested to learn your source for suggestion that Lexus 3.5 engine could require replacement timing chain at 70k miles. Whist just about any component in car may prematurely fail, the chance of this happening with the timing chain on this engine are miniscule and I would venture almost unheard of.  

 

 

 

 

 

 

 

[Delphius1]

Timing chains are regarded as non-serviceable items. There's nothing I can see that would indicate that would make it necessary to change a timing chain on a Lexus unless it's making a noise and you know something is wrong with it. 

If there's a known fault with the timing chain like there are with some BMW and Land Rover/Jaguar engines, then yes, it's prudent to change the chain and tensioner before they become an issue.

On a Lexus the timing chain can theoretically run for the life of the car and engine without needing replacement. Just make sure you change the engine oil and filter at the recommended intervals.

[Malc]

Nissan " for life " cam chains can also prematurely snap and cost £6k when snapped .............. engine destroyed ..... for life is often 100k miles in many manufacturers parlance .....  and nothing to do with engine oil, filter changes etc ......  nothing's for life really .....  except " life "

Maybe best to change the cam chains at max 100k mile / 10 years unless experience shows otherwise

Malc

[Barry14UK]

28 minutes ago, Malc said:

Nissan " for life " cam chains can also prematurely snap and cost £6k when snapped .............. engine destroyed ..... for life is often 100k miles in many manufacturers parlance .....  and nothing to do with engine oil, filter changes etc ......  nothing's for life really .....  except " life "

Maybe best to change the cam chains at max 100k mile / 10 years unless experience shows otherwise

Malc

Correct oil and filter changes will help minimise wear on pins, side plates and rollers on chain and also wear on sprockets with interrelated wear.  https://www.cloyes.com/timing-chain-system-frequently-asked-questions/#:~:text=The timing chain normally needs,common in higher mileage vehicles.

[m4rkw]

I wouldn't bother unless there are obvious signs of a problem.

[Delphius1]

On 1/24/2022 at 5:07 PM, Malc said:

Nissan " for life " cam chains can also prematurely snap and cost £6k when snapped .............. engine destroyed ..... for life is often 100k miles in many manufacturers parlance .....  and nothing to do with engine oil, filter changes etc ......  nothing's for life really .....  except " life "

Maybe best to change the cam chains at max 100k mile / 10 years unless experience shows otherwise

Malc

I refer to my comment above "Unless there is a known problem with the timing chain..." So far there's nothing to suggest that a Lexus timing chain will fail prematurely.  Toyota/Lexus timing chain engines seem to be engineered well enough that the chain lasts the life of the engine. There are no reports of premature failure on any of their timing chain engines. Toyota seem to get their engineering right, which is why most people are owners and are on this forum!

Belts are different because they are rubber items and have a mileage and age based lifespan. Usually 100,000 miles or 6 years, whichever comes first. 100,000 miles because that's the maximum mileage that Lexus recommend from a wear point of view and 6 years because that's how long the rubber can last before it starts to break down chemically. The same reason why tyres are date coded and have a lifespan of around 5 years.