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Do I need to replace coolant?

How hard is it to do a drain and fill on the 2009 mazda6 V6?

owner’s manual says Replace at first 190,000 km or 10 years, but car is only 5.5 years old has 125k miles though! do I need to replace coolant? it has FL22 long life coolant

Also last time i was at a shop i made the mistake of letting the mechanic top off the coolant without checking what kind of coolant it is…

I just checked the reservior today, it has quite a few small particles, dust or sand like floating in the coolant… what could they be, and coolant level is low again…

what happens if I don’t do anything, is the coolant due to be flushed/replaced?

Yes. Your owners manual should read;

Replace at first 192,000 km (120,000 miles) or 10 years ;after
that, every 96,000 km (60,000 miles) or 5 years

Use FL22 type coolant in vehicles with the inscription “FL22” on the radiator cap itself or the surrounding area. Use FL22 when replacing the coolant.

Unless the coolant was replaced during a recent repair (water pump or radiator replacement) the coolant should be replaced @ 120,000 miles and then after every 60,000 miles.

what happens if I stretch it to 150k miles? it’s only 5 year old car…

On the upside, nothing, on the downside a new radiator.

The manual for my Toyota said change the coolant after 7 years, then every 5 years after that.
What did I do? I changed it after 5 years (24,000 miles). The old coolant looked perfect.
I don’t care that I did it early. The coolant was a lot cheaper than the parts it protects.
Plus, I could simply drain and refill with the same Toyota coolant, a simple DIY job, no need to flush.
At 10 years I’ll change the thermostat, radiator cap and hoses.
My previous cars got coolant changes every 2 years, the green stuff.
Being able to go 5 years is a luxury in comparison.

I err on the side of caution

I think that 10 year initial coolant fill is pretty much hogwash . . . pure marketing

No more than 5 years for coolant


The cost of following the maintenance schedule is peanuts when compared to the cost of a new engine. I’m not sure what you think coolant is for. But one of the sure ways to kill an engine fast is to ignore the coolant. If the downside was only a new radiator then you’d be lucky. Imagine that the radiator clogs, the car overheats, the head warps and now you need a new head gasket and cylinder head work. Or imagine that before the radiator killing corrosion clogs the radiator, it rots out your heater core and your whole dash has to come out to fix that. Or perhaps it rots through a freeze plug, spilling out all of the coolant - overheating the engine, warping the head…Or it eats away the fins on your water pump, overheating the engine…etc.

Personally - I don’t care if a manual says you can go 120K or 10 years. Either one of those is way too long.

You’re due, it’s time and miles, you’ve gone the miles. Don’t cheap out.

And I would have the dealer change it, replacing it with factory fluid. If you do change type you have to make sure it’s flushed first.

so I can just do a drain and fill myself? I can’t even locate wher ethe drain plug is, is it easy to see?

the owner’s manual says it requires 10 qts of coolant. but if I do a drain/fill… some of the old fluid is still going to be in there so might not use up two galons i buy?

what about those dusts (black in color) floating in the coolant reservior, what the hell could they be?

There probably is a radiator drain but, it might be impossible to get to or just not worth the trouble. A lot of people just pull the lower radiator hose. This is messy, but fast and thorough. Wear eye protection. You should plan to have 3 gallons of new coolant around and you should plan to replace the radiator cap. The stuff floating in your coolant reservoir is most likely evidence of the beginnings of corrosion that is the reason you need to keep the whole system up to date on maintenance. You should also remove the reservoir and clean that.

Coolants are highly toxic but also attractive to living things - like pets. Don’t get anything poisoned. It also has to be disposed of properly. Make sure you have a plan for that.

If you plan to start doing your own maintenance, its probably a good idea to pick up a basic repair manual. You can usually find Haynes manuals at auto parts stores. They pretty much stink, but are mostly fine if you just need a reference for the basics.

Changing fluid is a very easy and very cheap insurance policy. And 5 years is “it” for me, no matter what the book says.

Personally, I find the easiest way to drain the system is to remove the plastic splash guards and pull the lower hose from the radiator or the engine end, whichever’s more accessible. When reinstalling it, the coolant even makes a good lubricant to slip the hose back on. I also always change the clamp for a worm-drive clamp … I personally find the OEM clamps to be a to use PITA.

Oh, and be SURE you use the right coolant for the car. There ARE different types, and they’re different for a reason. you do not want to mix them up.

I agree with cigroller.

My mustang has a petcock valve on the bottom corner of the radiator. It only unscrews several turns and then it drains. It doesnt remove fully (i learned that the hard way and snapped the old one! - easy replacement)

But if you cant find that, removing the lower radiator hose will be easy enough. Use some channel lock pliers, squeeze the hose clamp open and slide it back, and work/wiggle the hose off. It will gush quick so make sure you have a big empty drain pan ready, eye protection, plenty of rags and absorbent stuff helps to lay down.

Make sure the engine is completely cold (hasnt been run for atleast several hours) before you drain. Then reattach the hose, and top it back up to the cold level fill line. Allow air bubbles to burp out. Run the car and check for the next couple drives for any leaks or newly surfaced air bubbles - requiring a top off once the engine is cold.

Only check your level when the engine is fully cold!

Oh, and keep your heating system on when you’re doing all this. Most vehicles have a valve that opens when the heat is on allowing the fluid to flow readily through the heater core. If you don’t turn the system on, you just might have trouble purging (of air) and refilling the heater core.

would remove the lower radiator hose allow me to drain all the coolant??

can someone post a pic of where that is or what that looks like?

No disrespect meant Michael, but if you can’t find your lower radiator hose you’d really be much better off letting a mechanic do the work. We all can’t be mechanically inclined.

the mazda menu says coolant capacity is 10 qts or 2 gallons, how many gallons do i need to bring to the mechanic? would a drain/fill or flush require less or more of the specs?

mazda dealer wants $25+tax for each gallon 0000-77-508E-20 Coolant Fl22
can i use alternative FL22 coolant?

dealer wants 160 for a complete flush and 99 for drain/fill… so much $$

can I use FL22 coolant from autozone without getting it from mazda dealer or do I have to use the mazda coolant?


Nobody except Mazda carries FL22 compatible coolant

My brother has a Mazda which also calls for FL22, and I already checked if anybody else carries this stuf . . . no such luck

Don’t use any generic and/or universal coolant