Steering You Right with Sharon Peters: Flush Facts

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Q: I have a 10-year-old Hyundai Azera and after my oil change I was advised to flush my power steering, transmission and brake fluids. How critical is flushing instead of just replacing the fluids? I've received flushing estimates in the $600 range and would think draining and adding back new fluids would be enough.

A: There are different opinions on these matters, even among mechanics I trust.

There’s some maintenance I do sooner or on a grander scale than the manufacturer recommends because I do a lot of mountain driving and I live in a dry, dusty area. Draining and replacing transmission fluid is among the things I rev up a bit, though I’ve never flushed it, and my vehicle, like yours, is nearly 10 years old. Generally, I’ve concluded, it’s safe to follow the owner’s manual and not give it another second of worry.

Here’s what the 2007 Hyundai Azera manual says: Replace transmission fluid at 105,000 miles. Absolutely no mention of flushing. I’m guessing you have at least 105,000 miles on that vehicle, so you’re due.

Your manual also says if you do “severe driving” you should replace transmission fluid every 30,000 miles. Severe means you drive lots of short trips; live in very cold or very hot climate; do uphill, downhill or mountain driving; or haul something. Still no mention of flushing. Indeed, some manufacturers specifically advise against flushing (though I didn’t see anywhere that Hyundai does).

It’s worth noting that many of the mechanics I trust say 50,000 miles is as much as you should go before changing out transmission fluid, even if you don’t do “severe driving,” as the fluid deteriorates with time.

As for the brake fluid, Hyundai says to inspect it every 30,000 miles and replace when necessary. No mention of flushing. Again. Some other manufacturers say replace brake fluid every 45,000 miles; some say every two years; some say every three years. But I found none that recommend flushing unless something – perhaps extremely humid conditions – corrupted the brake fluid.

As for power steering fluid, Hyundai makes no mention of replacing it, just of topping it off when necessary. None of the 10 manufacturers I checked listed flushing as part of routine maintenance.

Sharon Peters What’s your question? Sharon Peters would like to hear about what’s on your mind when it comes to caring for, driving and repairing your vehicle. Email Sharon@ctwfeatures.com.

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