what is the service life on these, was thinking about changing it as preventative maintenance

cant really see to inspect

they never seem to mention changing them, I did mine when the alternator went south at about 68k, the old belt didn't look too bad to be honest but they are fairly cheap, a bit fiddly to change though. There is nothing that can't be fixed with a hammer😜😜
FFRR 4.4 SDV8 Autobiography Santorini Black.
KIA E-Niro 4+
2021 Discovery 5 D300 MHEV commercial

Hi there.
I changed mine a month ago.
Intercooler hoses off.
Top water pipe off.
Airbox out.
Fan cowling unclipped.
Left hand thread on viscous fan.
I downloaded a whole heap of serpentine belt routing diagrams on a PDF and used it for reference.
My 2007 vogue has done 216,000kms and I don't think it had been changed,then it snapped,only half the width of the belt was in the guarding.
I think the steering,charging etc is now much better.

thanks for the info on the change, its now on my short term list

I had mine changed and the idler pulleys replaced when the alternator failed at about 70k miles

what was the condition of the belt ?

Dealer said belt was OK but as it was so hard to access and it was not expensive I had it changed anyway.

I'd always chuck a new one on there just for peace of mind if i was replacing anything else they required it's removal.

It's a bit like replacing a clutch when a gearbox or engine is removed for something. For the sake of the parts cost it'd daft not to.