Coolant check during servicing

[Jim MacDonald]

Having just had my car serviced (6 year old Prius, gold service), I note there is no line on the Toyota checklist for the condition of the engine coolant, only for replacing it after 3 years/40,000 miles or (much) greater intervals depending on engine type.  Memories from my youth are that this used to be part of the annual service of any car, particularly during the winter months.  The received wisdom in those days was that the effectiveness of the anti-freeze would diminish over time.

Am I out-of-date in some way?  Perhaps the formulation of the anti-freeze has been improved, the way the coolant is circulated through modern Toyota engines is better so that the coolant doesn't deteriorate so quickly ... or we were all duped about the necessity of annual checks in years gone by?

Actually, I asked the Jemca gentleman whether the coolant had been checked and was ok for the winter.  He assured me it was ok so, if I take his word for it, it is checked - but, if so, why isn't it on the checklist?

[FROSTYBALLS]

The standard replacement for the factory fill of Toyota Super Long Life coolant is 10 years/100,000  miles, with subsequent changes thereafter at 5 years/50,000 mile intervals. 

Presumably the formulation is greatly improved over previous generations of coolant.

[Jim MacDonald]

Great to get an answer from someone calling themselves Frostyballs on the subject of antifreeze - you're clearly the right man for this subject !

Further web searching supports you are right about the formulation being greatly improved in recent years, for instance see http://www.coolantexperts.com/coolant_overview/oat_coolant

I'm glad to see that link also refers to regular topping up with antifreeze during servicing in days gone by, so at least that supports my memory of how it used to be.

That still leaves me with my original question about checking the coolant during the service.  Perhaps it is covered by the line at the bottom right of the checklist "Re check All levels" which has been ticked for my car service.  And perhaps the Jemca gentleman knew about modern anti-freeze duration and that level checking was sufficient for him to be able to say my car was ok for the winter.