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All of these flush recommendations

It seems every time that i take a newer car in for vehicle inspections or free oil changes, I get told that I need either a cooling system flush, break fluid flush, power steering flush, fuel injector flush etc. because of the mileage. I was always taught that you dont need to flush until the fluid has deteriorated in some fashion. I have kept cars for years with that philosophy.

Have things changed and I have not kept up with it? or are the shops just trying to get another 100 out of me?

Thanks in advance


Always check the OWNER’S MANUAL, that little book determines what your car actually needs in terms of maintenance. Flushing is fast, profitable and requires few skill on part of the service shop. Therefore they push it.

Most old timers here recommend against flushing transmissions; simply dropping the pan and changing the fluid and filter every 50,000 miles will ensure long transmission life. Cooling systems used to need flushing, but with today’s high quality coolants, simply draining and refilling is sufficient, provided the drain interval specified is observed. My Toyota manual has no “flushing” instructions at all.

Ignore all those “flush” scares and read your owner’s manual first.


Those repair shops can’t make their money off of you with free oil changes or inspections. They’ll pitch whatever they can at you hoping you’ll bite.

Before you do bite, follow Docnick’s suggestion of checking your owner’s manual first. You may also want to have the work done by a mechanic who is less eager to sell you unneeded services.

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My 2005 Accord requires coolant change at 105,000 miles to coincide with the timing belt change. Transmission fluid and brake fluid are as needed, but I change them both at around 40,000 mile intervals. I have almost 180,000 miles in the car, and both the transmission and brakes perform well.

Mostly they are ‘wallet flushes’; the owners manual will tell you what is NEEDED

Unless you’re due as indicated by your owner’s manual schedule, or you’re having an operating problem, the only thing these flushes do is prevent you from building deposits in your bank account. They do nothing for the engine.

Here’s another vote for following the owner’s manual.

I change my fluids at regular intervals. Cheap insurance IMO. Even my 02 tundra has been known for a pink milkshake issue where the tranny fluid line can exhibit galvanic corrosion due to dissimilar metals used at the radiator junction causing it to mix with coolant as it passed through the radiator. . I suspect not changing coolant at regular intervals can exacerbate the issue. I changed out my radiator at 160k with zero corrosion which i suspect is due to regular fluid change intervals IMO.

My father who’s been wrenching cars for 50 years before retiring is the exact opposite and only changes his oil and has 140k miles on his 95 ford rsnger.

Your owners manual will specify the interval for replacing various fluids and lubricants. In most cases, it calls for a drain and refill, not a flush. Most of us however recommend that you do a drain and fill of the automatic transmission every 30-50k miles even if it is not listed in the owners manual.

Most new cars do not have a dipstick or fill tube for the transmission anymore. Some cars even require (according to the dealers anyway) a special machine to fill the automatic transmissions, so a drain and fill can be quite expensive.

Brakes, however, do need a periodic flush. You want to flush these to avoid getting any air into the brake system. The owners manual will list the interval. If it doesn’t, then most brake shops will recommend flushing the brake lines when you get new brakes and I would concur with that. But unless specified different in your owner manual, I would not flush the brakes except when getting new brakes.

You’re right about lack of a dipstick, or even a dipstick tube, for that matter. I mentioned the dipstick tube, because in the past, Benz transmissions had a dipstick tube, but the dipstick itself was an extremely long flexible special order tool, with markings on the end.

However, a speed sensor or plug on the side of the housing can sometimes be removed, for the purposes of refilling the fluid. And it is generally possible to refill through the drain plug opening. Both methods require

That still leaves the matter of checking the fluid level at the correct temperature

OP is right to be concerned they’re being subjected to a marketing ploy. But on some vehicles some of this, or all of it, may make sense. Suggest to consult your local inde mechanic for their take. Preferably someone who has worked on your car service and maintenance quite a bit already.