Hi all,
I am preparing to change all the coolant hoses on mine 4.4 ajv8 due to its age (15 years) and miles.
Does anybody had problems with this pipe (connects thermostat housing with the engine) which is made of plastic? I am thinking if would it be smart to change it preventively when I change the hoses, but don't know if it is prone to cracking? Mine still looks good visually.

 RR HSE 4.4 2006 LPG

That looks like a nice job . Mines the same age as yours & not had any issues with the pipes or hoses.
I changed the thermostat the other day & to be honest the pipes looked good. I do change the clips every time I undo a hose though.

My thermostat housing was cracked (probably by the garage whilst replacing my inlet manifold). It led to the engine running too cool and hindering DPF regens and restricted power.

Took a while to find it, so yes, change it if it's cheap part and you are disconnecting it anyway.