When the computer throws the code that you need to change the sensor.
You need to flush the power steering fluid on a 2003 Toyota Highlander every two to three years. You should check the fluid levels weekly.
I have found that the filter should be changed around 90K in normal use and 60K in severe conditions. Toyota Tech.
You should change your automatic transmission fluid in Toyota gearbox at least after every 30,000 miles.
you should change oil on you car every 5000 miles
every 30k miles
Each 5k miles.
Change it every 75,000 miles.
The only answer I can find in the manual is when the dashboard "maintenance required" signal appears. I'm thinking it's around 5000 miles, but I don't know for sure, as I just got my 2005 Highlander recently.
Every 8000 km,or 6 moths.
Every 15,000 miles.