3.9 knocking noise advice

Hi my motor is delve oping a knocking noise. It's a dull noise like a spanner tapping the block. It's only apprent when cold and dissaperes once warm. It worsens under load. Due to the frequency of the knock i'd say the problem is only on one cylinder. What do I need to check? Starting with the easy things first please.

My thinking is that a worn cam would be noisy when warm too.

What do u guys rekon?

Rocker arm lazy follower

Just change them all?

Few, I thought someone was gonna tell me it was a slipper liner....

it could be , start with the cheapest options first though mate

flush the old oil out and put some quality oil in the engine.
See if that makes a difference

So is it best to just replace all the followers and rocker arms? Or diagnose which it is just just change tha faulty one?

Should I do the cam shaft and timing chain while I'm there? Or is that a bit over kill lol

joe1972 said:

flush the old oil out and put some quality oil in the engine.
See if that makes a difference

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Done that. Made no difference really. But it does seem to get a big quieter with 15w40 instead of 10w40. I'm back on 10w40 now though.

my 3.9 got noisier on 15w40 or thicker

10w40 was the best for it

the 3.9 and bigger rv8's are crap though, both for noises and hgf/slipped liner woes-never again :doh:

best to get the noise listened too no disrespect but guessing will always cost more and it guess sometime right sometimes wrong

vougese39 said:

best to get the noise listened too no disrespect but guessing will always cost more and it guess sometime right sometimes wrong

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Can u move to yorkshire please....? lol