I normally change my coolant every two years, however I've had the suspicion that I could probably go longer. With that in mind I just bought a 50 strip container of Castrol coolant test strips. On special $10.00 off at Repco for $23.00. The bottle has two colour test charts on the side of the container. One shows percentage of Glycol the other shows corrosion protection. I did a test and both tests were at the top of the chart. So I'll leave it for another 12 months. 
Regards Martin.

Never seen them before

They've been around for a fair while. I just thought I'd give them a try and I think judging by the reading I got I can probably go 4 years plus. I do believe if you look around you can get them in a smaller quantity. They're only good for around two years and I'm unlikely to need 50 in those years. I should set up a testing service with the leftovers.
Regards Martin.

Since a coolant change only costs me $6 every two years, it's not really a big deal. 

We also have a dehumidifier that runs in the summer creating massive amounts of free distilled water.

Most coolants last about five years these days. (As long as you use distilled water since tap water has impurities.)

I test mine by licking the radiator cap. Yummy.

duck wrote:I test mine by licking the radiator cap. Yummy.

I changed a water pump in my Mum's VW Rabbit diesel on a cold January day with a layer of compacted snow all over the driveway. This was back when I was under 30 and could take the cold better than at age 60. Anywho, I cleaned up job done, tools away, fingers thawed, whikkey bottle open inside by the fire, too late to drive home 35 miles away, free dinner, but didn't notice the splash of old coolant now blended in with the packed down snow and ice beneath the car - but the free range, wandering chooks did before being put away for the night. 

Next morning, exclamations of unhappiness from Mum from the kitchen window. Did a fox sneak in at night? Nope, the yardbirds located that old coolant quick smart and had a good ol' peck at it. Damn near cleaned it all up. It sure cleaned them up, too. About four out of ten chooks dead, frozen. They did not go into the freezer as next Sunday's roast.

It's lethal to cats too.

And husbands. As a few have had the misfortune to not find out until it was too late.
Regards Martin.

And cane toads 

Left a bucket sitting out side the shed when I drained the radiator from the prang 

Bloody toads jump in dead the next day left them sitting for a little while longer and more jumped in 

after a couple of days the smell was gone and so was the toads

Dai wrote:It's lethal to cats too.

Feral and unconfined domestic cats are the worst predators of small Australian native animals and birds, accounting for literally billions each year. So perhaps I should leave some out . . .

Bill