On Sunday, October 20, 2019 at 4:15:59 PM UTC-4, Ralph Mowery wrote:
In article ,
says...

Decades of experience here with many cars. You know how many
I flushed? None. How many problems did I have that were attributable
to coolant? None.




I gave up years ago on changing the coolent. Just add some if it needed
it. I did get it changed about every 70 thousand miles due to having to
have the timing belt changed on my Toyota. At the same time I spent a fe
dollars more to replace the water pump as it was behind all the belts
and gears and the mechanic only charged his proce for the pump.

Put 200,000 miles on that car and never had a coolent problem.

Same here, rarely some repair required draining the coolant and if the coolant was maybe 5+ years old, I would replace it. Did the water pump preemptive replacement on the BMW-X5 and regretted it. They used plastic impellers and there were lots of reports of them breaking apart, pieces getting stuck in bad places, etc. So had to do an alternator and put in an aftermarket water pump with metal impeller at the same time. That had a bearing failure at 50k. The original looked fine and might have lasted longer.