2006 Prius approaching 142k mileage. Any recommendations on maintenance or prolonging its life? No known issues as of right now. Below is summary of my ownership. If it’s not listed, it’s probably original to vehicle (excluding oil and filters). 2021 Spark plugs, PCV valve, coolants, trans fluid, clean Hybrid battery fan, brake pads and rotors 2022 OEM hybrid battery 2023 12V battery, front headlight bulb 2024 Tires, inverter coolant pump, front wheel bearings
Change brake fluid? Check the mechanical water pump belt. Not sure how it is in Iowa, but if that was the original belt in S. California it would likely have a bunch of small cracks from the heat. Inspect the hoses in the engine bay. Check the spare, the pressure is likely low. Unclear to me if donuts ever go bad, they don't see any sunlight and are protected to some extent from ozone, but they do get baked when the car is parked in the sun. That said, the bottom of the trunk area with a metal interface to the shade under the car should be significantly cooler than the cabin of the car under the same conditions. Probably for similar reasons I have measured the 12V battery at about 10F cooler than the cabin. Check every bulb on the car. (Possibly avoiding a ticket for having the rear license plate not lit?) Easiest to do on a lift, but the components on the bottom of the car should be inspected from time to time. Failing that, at least bounce each corner to verify that the shocks are still functioning and there are no unexpected sounds when the suspension components are moving.
Is it too late to change the brake fluid? I don’t want any risks of the expensive brake actuator replacement.
That is the debate. I had mine done recently, but it was a bit of a special case. There is a problem on my car with the front driver's side wheel running slightly warm, and when I had the "this is the guy you go to when nobody else can figure it out" mechanic trying to diagnose that problem I had him change the fluid at the same time, since he was going to relube the brake pins to see if that resolved it. He had the right tools to fix the problem if the brake actuator detected an issue from the fluid change and had a hissy fit, and I didn't. As it turned out he couldn't find the source of the heat either, and it remains to be seen if the fluid change will cause the actuator to fail prematurely. (One possible explanation is that the actuator is already failing and is causing that brake to drag ever so slightly, although not even enough to cause uneven wear between the pads on the two sides. The more likely one is that the bearing that was replaced there wasn't very good.)
It's a throwback from a time when a vehicle needed all its fluids changed regularly. We don't live in those times anymore. Also some people on here a convinced that the $2K part that runs the brake system is more likely to fail and will need to be replaced after a brake fluid change. For this reason I have 300K miles on original brake fluid and still haven't had any issues.
Even so, brake fluid should be changed every two to three years. You can buy a brake fluid testing kit and change it as required, if that's more your bent. Brake fluid is hygroscopic, and once it has absorbed enough moisture, it is not kind to the internals of the brake system. Regular changing of brake fluid will be beneficial for the brake actuator, even if it has been a while. I wouldn't let an old wives' tale hold you back.
There are two issues with changing the brake fluid on this vehicle: 1. Unlike all the other cars I have owned the Prius is touchy about its brakes, and if things go a little sideways the actuator will throw codes and special software (and hardware) is needed to dig out of that hole. Techstream will work but not with the miniVCI cable most of us have. Apparently the Autel AP200 will work reliably for this. 2. There are reports and rumors that changing the brake fluid can cause the actuator to fail a "short" time later. Toyota might have enough statistics to say for sure one way or the other, but I'm pretty sure nobody outside the company does. I certainly have no way of determining the truth here. There is a fair chance that this danger is complete BS, based on a few cars where the actuator failed in that time frame, because brake actuators do fail on this car on a time frame (long) that is similar to the "I really have been putting off changing the brake fluid too long" time frame.
I suspect that most reported failures that drive the rumour-mill are caused by DIY incompetence. Yes, you certainly need the right tools and process knowledge to do this right, but that's what you pay a professional to do if you don't have the prerequisites to do it yourself. The last time I did it, I paid my local Toyota dealer NZ$165 (so, ~US$95). Well worth it to me. That was over two years ago, and no issues at all.
