Extended Life Coolant Query?

I've had the same ELC in my 9U tractor now for 7 years, on average it's only done 2 days of work a year over this period. Can anyone confirm how often it should be replaced?

Thanks, David

Cat has a test kit #223-9116 ELC Dilution Test Kit. I'd recommend you test your system.....seems I recall five years is about the expected life but I suppose as long as things test Ok it's still good.

OM, many thanks for the prompt response. It's starting to get cold in the UK so I thought it would be good to check whether Its time to change the ELC before the traditional deep freeze start in the new year. No doubt the KOO would regard a UK winter as just a mild frost in the Kingdom!

Piffle! Koo would consider it a pleasantly cool temp, suitable for an evening cook-out! ; )
The farmer's almanac is predicting a heavy winter this time round I understand - here in Rochester NY, our last winter was pretty mild. We did have snow last winter but not much and we didn't get the std. two weeks in the twenties. I'm hoping it's going to be cold because we signed up the kids for the local skifield and I need a return on my investment! : )
Makes working outside on the tractor a bit of a chore though...
Cheers,
Neil.