Ace fluid

Hi guys
2008 RRS 2.7 Hse

Ace system.isnot leaking just sitting below maximum.
Garage said today to add this to it
Lucas Hydraulic Stop Leak Additive. Although not leaking he said it Reduces Heat & Friction so will keep seals intact and will help the system as they are known for failing
Is this true or not.
Thanks guys.

If it's not leaking I would not add anything that claims to stop leaks, stick to the correct fluid IMO.

+1, if it ain't broke, better to top up with the correct fluid and keep and eye on it every service to be sure, to be sure