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Changing brake fluid or power steering fluid

My wife’s mechanic tells her she needs to drain and put in new brake and power steering fluids. I cannot find any mention of this need in the maintenance schedule for her Mercury Mountaineer. Also, after many cars and almost 50 years of driving I have never done either. What gives?

Brake fluid should be changed out at a specified interval, due to its hygroscopic nature. I have never changed out power steering fluid unless I had to do a repair. I am surprised that your maintenance schedule doesn’t mention the brake fluid, though. I would change the brake fluid and leave the power steering fluid alone.

You can also use a turkey baster to take out a selected amount of PS fluid and replenish, drive the car and repeat. Many folks do this to replenish the PS fluid.

Brake fluid, yes. This is especially true with ABS systems. Power steering fluid, no.

A cheap siphon pump will work a little better than a turkey baster.

My car also has no interval for changing the power steering fluid, but all fluids break down, and I think changing it every once in a while is a good idea. However, I don’t recommend you pay someone to do it. The price is often quite inflated.

Changing the power steering fluid helps to keep the seals in the power steering system soft and pliable preventing them from leaking. Which would you rather pay for? A power steering fluid exchange? Or a power steering pump/rack and pinion assembly?

Tester

The cost of having your power steering fluid changed is usually about $40, so in the grand scheme of things, I would rather pay to have the fluid changed. However, I can change it myself for less than $10, and it isn’t a job that requires mechanical skill. You just pump the old fluid out, and put the new fluid in. In the end, that’s all they’re charging you for. They don’t usually have a special pump or machine.

I have a special machine for exchanging ALL the power steering fluid.

Tester

I change brake fluid every 3 years. I drain & refill the PS reservoir once a year.

Jerry, the reason for the brake fluid change is that the fluid absorbs water and that water can and will rust the metal brake lines and in time it could rust to the point that it breaks and therefore, no brakes when you need them. I have seen this happen.