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Do you need to change power steering and brake fluid? And what is the best way to change transmission fluid flush or drop?I read on line some manufactures don’t recomend that you flush them out.

I change the brake fluid every couple of years or about 30,000 miles. It absorbs moisture over time and becomes less effective ifit overheats. I’d drain and refill the transmission fluid, especially if you haven’t been changing it every 30,000 to 40,000 miles. The issue is that if there are metal shavings in side the transmission, a flush will move them around. The particles could become stuck in a valve and prevent complete closure.

If you’re DIY’ing your brake work, then a 2 year change out isn’t out of line, especially if you have ABS. Otherwise you’re getting it serviced every 2 years anyway and a professional is bleeding the brakes. This refreshes the fluid well enough. It may be recommended NOW, but last time I checked (somewhere around 2005) no domestic manufacturer has included this as scheduled maintenance. Ask an older mechanic that stopped bothering to “buy up” to account for the state of the art and he’ll tell you he’s never heard of flushing brake fluid. Now he may have had to totally rebuild some 4 piston Vette that sat for years in a garage without moving, but never for a daily driver. They get enough routine fluid swapping.

On the trans, I really don’t like the term “flushing”. It is too easily associated with solvent cleaners. I prefer the term “exchange” which sorta leaves no doubt on what you’re doing.

I prefer both for the initial service session. You start the exchange and drop the pan at the first evolution where you would normally add fluid. That’s so you have an almost empty pan and don’t have to tap dance to keep the fluid from getting all over the place. After you button it up you just complete the exchange. You then should never have to drop the pan again. I like to add auxiliary filtration. A magnefine or Filtran in line filter is a nice added touch. They’re about $20.

There’s no different action between normal operation and a fluid exchange. Whatever is sitting in the pan …will stay exactly where it was.

On the power steering I like to change out. Some units (Ford in particular - some anyway) have a high friction/wear system that benefits from fluid changing. Some Fords come with a magnefine from the factory. It’s sorta hidden, but is standard on Taui (multiple Taurus?).

I like to use synthetic for both the trans and the PS.

The brake fluid is a must. It is a safety issue.

I would (will) do when I am working in that area.

The transmission fluid I would do every two years or 40,000 which ever comes first. Do a drain then drop the pan to clean the filter.

It is a good idea to give us as much information as possible. What model year is your Montana and how many miles on it. Are you the first owner?

In any case look at your owner’s manual and that is your minimum.

I have to disagree in the safety issue. As I said, it may be NOW, but it’s never been in ANY domestic owners manual as routine maintenance until the last half decade. How did the domestic OEM’s avoid being owned by the Bar Association for NOT recommending this for the past 50 years?

It’s a system longevity issue.

It could be that years ago cars typicallly only lasted 100,000 miles and now last far, far longer.

Or it could be that many years ago the world was not plagued by parasitic lawyers and bad tort decisions.

Mainly we were not plagued with the industry self promoting excessive services that were not needed …yet evolved to “must do’s”.

This is a somewhat natural evolution in anything. Do you think design engineers are going to close up shop and quit when they’ve reached some sensible ROI on stuff? No. They’re going to pull smaller and smaller rabbits out of their behind that cost more and more $$$ to produce.

Do you really think that Dex VI was “needed”. The same transmissions had worked well with Dex IIIH …but create it they did. I happen to know (internet “know”) one of the GM power train fluid engineers that developed it and co-authored a GM sponsored research paper published by SAE. The publication showed the performance advantage of OEM fluid over multi-vehicle fluids.

So a GM sponsored study, done by GM power train engineers …concluded that GM’s newly developed fluid produced superior performance when compared to multivehicle fluids.

Who would have imagine that?

It’s the same with child safety seats and propane tank valves. They both get an industry lobbyist to get legislation to make the former improvement obsolete. The child safety seat costs (my guestimate) BILLIONS in ancillary costs since it made every 3 child family buy a mini van or SUV since they could no long fit 3 seats side by side in the average sized car.

Now surely everyone wants to save lives, but if you put the additional saved lives in a room …and then said, “you can save these lives if you can raise $750B by 5pm tomorrow” …those lives would be gone and we’d think it was a sad event. This way, we don’t have to make those choices in how we fund the saving.