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Are flushes really necessary?

Why are repair shops now advising car owners to get all the system’s flushed; as in the transmission, brakes, coolant, steering fluid, power, and steering fluid systems? My car is a 2009 Nissan Murano with 60,000 miles. Is this really necessary if there are no obvious issues with these systems? Is this just a money making thing for the auto shops?

Yes, just to increase profits.
Carefully follow the service schedule in your owners manual. The items you noted above do require maintenance.
It is the term “flush” that is ambiguous. This could mean the use of a chemical, which may do more harm than good, whereas changing the brake fluid does flush out the old fluid with new.

Of all those listed, flushing the brakes and cooling systems are by far the most important on your vehicle. Coolant ages with time, not mileage.The additive package in the fluid keeps the internal pathways in the engine from corroding.

Same for brake fluid. Especially true for brake fluid. Brake fluid absorbs water from the air over time and will corrode the brakes from the inside out. You 10 year old Murano should have had the brake fluid flushed at least twice by now.

I would also suggest a fluid and filter CHANGE, not “flush” for your transmission because you have 60,000 miles, not because it is 10 years old. Preventive maintenance is cheaper than a repair.


I second everything that @Mustangman said. Including just a Fluid and filter change on the transmission


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If a flush is recommended then it’ll be outlined in the manual.

I don’t know too many manufacturers who recommend a Tranny flush. Usually just a drain and replace.
Coolant - Yes. but most these days are 100k miles or more.
Brake fluid - again yes, but not at 60k miles.
Steering fluid - yes, but not at 60k miles.

But remember this is 10 years old.


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Missed that. Then yes…it needs changing.

Almost all manufacturers recommend transmission flushes.


That was more of an advertising for a tranny flushing machine then what manufacturers recommend.

No vehicle I’ve owned in the past 30 years recommends a tranny flush. In fact they recommend AGAINST a flush. Only a drain and fill. There’s a transmission place next town over I use…and almost every dealer (domestic and foreign) send them their big transmission work because the dealers don’t have the expertise in-house to do the work. This place is big (15 bays), and all they do is transmissions/transaxles and transfer-cases. I asked if they do recommend a flush or drain and fill. Said they use to have a flush machine…but no manufacturer calls for a flush these days. Just a drain and fill. Between the mechanics and owner there’s over 200 years of combined experience in that shop.

Not really tranny flushes, are they? Aren’t they fluid exchanges, where the old fluid is captured as the new fluid is added? I wouldn’t have a problem with that.

This probably has to be the simplest flush machine ever produced.

You connect it between a transmission cooling line and the radiator.

You then fill the clear cylinder with fresh transmission fluid.

You start the engine, and the pump within the transmission pumps the old fluid out which applies hydraulic pressure to a piston at the bottom of the cylinder, which is forced up and pumps the fresh fluid back into the transmission. This is continued until the fluid coming out of the transmission is the same color as the fresh fluid going in.


But you have to be careful to distinguish that kind of machine from the kind that forces new fluid under pressure into the transmission while forcing old fluid out. That can cause issues.

You also have to make sure that the garage is actually using their machine. There have been exposes over the years, particularly with the quick-change shops, where they will charge you for the service and never even hook the machine up.

The article describes adding a flush agent to dissolve varnish etc and running it for a time before performing the fluid exchange. That’s what I would call a flush vs a fluid exchange vs a drain and fill. I also would prefer the exchange as more of the oil fluid is replaced than by a simple drain and fill. Not a big fan of solvents unless there is a known issue…

2007 Nissan Altima’s ESM specifically calls for “flush” (AKA “inline fluid exchange”) method for their CVTs, so I would assume Murano has similar procedure. They do have a plug, but ESM calls for flush.

Now, Nissan CVTs of pretty much all generations have high failure rate, in my family I had 1 CVT to fail hard, 1 which started to slip and it was sold, 1 is still going at 105K miles.

I would concur with @Mustangman and @Yosemite on filter exchange, but I would also either “flush” ths CVT or make two rounds of drain&refill to get rid of as much old fluid as possible.

It definitely benefits the long-term life of the car to replace the fluids with fresh versions from time to time. Just make sure it is done w/ an an innocuous method. The word “flush” would make me worry what they intend to do, but the phrase “drain and re-fill” wouldn’t bother me.

Well we’ve gone round and round on this before and we are never going to agree so just do what you want. Acura says drain and fill. The shop I’ve used for over 20 years says drain and fill. That’s what I do.

Here’s a guy that says drain and fill or if you want to flush, do it as long as the fluid is in good condition, otherwise you’ll be removing particles from the clutches and cleaning the valve body that can cause a problem.

The last thing you want to do with a transmission is remove any particulate from the fluid that can contaminate the valve body and solenoids causing shifting problems and slipping.

Are you for real?!


That was a quote from the youtube.

Edited to be a gentleman.

I’m to ask you straight out Bing.

How long have you been an automotive technician?

Or are you another computer chair mechanic?


Edited: OK, that was a little harsh on my part.