Gary is correct. Brake fluid is hygroscopic, this contaminates the fluid and reduces it's ability to do it's job. However water, when compressed changes forms, from what I understand, which is why the fluid is that way. Having moisture buildup in the brake system and then turn to air when you hit the brakes would be very bad.

I do agree, with a 2 year flush the system stays extra clean, and nice. however would it be the same with a 3 year plan? Maybe, I haven't really looked into it. Do I flush brakes? Absolutely. I made a presssure bleeder from a garden sprayer, one of those brake reservoir caps from the 'HELP' line of off the shelf auto parts and an fitting from the local brew supply store. (Note, I was only in the brew supply for the fitting, not for brewing material.. uhhhh). The pressure bleeder not only makes flushing systems possible, but also bleeding brakes is a breeze. Also, if there is a problem, the pressure bleeder will cause the faulty part to fail and in a safe enviroment, ie not on the road. Just pump it up and wait for the fluid to flow clear through into the catch bottle. After doing a few of them at MB, it's very easy to tell when you have clear fluid coming out. The setup I have cost less than 20 dollars and helps keep one piece of the vehicles I own clean, neat and worry free.

I think the safety aspect is one reason MB likes to replace the fluid every 2 years. After all, if you drive an MB, you are two busy and important to sit on the side of the road or deal with those pesky brakes going out. At MB they use an electric powered bleeder that they shop purchased that does a great job of pushing all the fluid out. Even on the brake by wire systems that they have.

 

Josh - That system to bleed the brakes sounds like something I'd like to make. I've tried several approaches and have had problems with all of them. Could you post some pics? I don't think the OP will have a problem hijacking this thread.

 

Water doesn't change forms when compressed, however it will turn to steam when heated. As in heavy break usage or freeze during cold weather and will rust or corrode components, depending if they are steel, aluminum etc. This is why you don't want moisture in your brake system or any other place that requires lubrication.

 

I'm not saying that water in the brake system is a good thing, or that brake fluid doesn't absorb water. Simply that I've never seen or heard of a failure attributed to not changing the brake fluid every few years. I noticed no improvement in braking performance after changing out the green brake fluid in the Excursion.

It was worth doing due to obvious contamination, but remember this fluid was 12 years old at the time. If once in twelve years was enough to avoid a failure, why should I do so every two or three?

 

Hold on boys, I thought this was about Ecoboost towing? Heheheheee, well, I'll be towing our 25' 3,200 lbs empty travel trailer 800 mile one way trip soon. So far, I only towed it 20 mile Ecoboost test run, 10 miles down road and back. We've had this trailer since new, '98, and towed it thousands of miles. Loaded I reckon it's 4-5,000 pounds. My '15 3.5 Ecoboost should pull'er with no problems. We go through Arkansas hills. My '02 5.4 did good, so I'm looking forward to Ecoboost drive. Oh, and all this mpg talk? My '02 got about 9-10, so I'll be happy with new F150 for sure. And, wow, I love this 36 gallon tank!

 

Keep us posted - on here if you'd like.

 

Gary,
Sorry for taking so long with getting you the pic of the system I use at home. However at this point, rather than build one, I'd probably just buy the fifty dollar one off of amazon, and then get the right adapter for my needs, or maybe even be spendy and get the whole collection of brake reservoir adapters!

Here is a link to the one we used at MB: Expensive Bleeder
http://a.co/1TdqHaY

link to a write up, as I'm too lazy to do it myself: WriteUp

Link to a pre-built manual bleeder: http://a.co/2GeYdtd

 

Josh - Thanks! This is very timely, oddly enough, because I just acquired a 1985 F250HD that has a working brake system but yucky-looking fluid. So, I want to flush it but am NOT going to try to suck it through with a Mityvac.

And, I fully agree - buy the one off Amazon instead of making it. But, on the adapters, is this the one you meant? https://www.amazon.com/Motive-Produc...HY8TCF1Y0NCTA9.

 

Worth it just for the adapters. I had not seen that one. All the adapter kits I found were 2-300 bucks, ergo why I built mine, since I planned to make all the adapters as well.

http://a.co/9ohNRCC

http://a.co/1XOUNKN

However with that setup, it looks like it would be easy to add additional adapters, just find the right AN fitting to screw in. I also don't see a shutoff valve. I would add one, in line, as close to the adapter connection as possible. to stop fluid from dripping. Remember when you disconnect, without a shutoff valve to relieve pressure. (Yes I have done it the other way, there is brake fluid on the shop roof to prove it.) Oh and don't forget your turkey baster or fluid evacuator, they will leave the system over filled, and you'll need to lower the level just slightly.

This is what I use: http://a.co/0ReL4GC

I used to use a turkey baster\suction bulb 'designed' for brake fluid, however, after ten years of being saturated with brake fluid the rubber expanded and didn't seal on the intake tube. I've not been able to find another one, as that came off the S&K\OTC\any cheap tool he could sell\specialty truck, in fact I almost bought a Taylor 6 string off that truck...

Since I showed off my old evacuator, I'll show off the one I currently use for oil changes

http://a.co/av8Hj9T

yeah yeah.. I'm sure someone's gonna say they don't trust sucking the oil out when there's a perfectly good drain plug on the oil pan for that... you know the thing that strips out\can crack the pan\some cars don't have\some cars have two off (though I personally have never seen more than two).

 

Josh - I think I'll go with the one in the link I gave. Thanks. As for the turkey blaster, mine has a number of turns of teflon tape around the neck of the bulb where it goes into the intake tube, so I understand the problem.

As for the oil evacuator, I use a hand-operated one, but only on my boat. The drain plug on the Chevy 6.2L is almost against the hull, and even if you could get to it the oil would make a huge mess. So Mercruiser installed a dipstick that goes essentially to the bottom of the sum and has a garden-hose connection on the top. Hook the pump to that and it gets almost every last drop of oil out w/o a mess.

 

Hadn't thought of the teflon tape. i'll definately give that a go if I can find the old bulb. Also hadn't thought about boat applications for the oil evacuate. With out shop air mine wouldn't work.

So much about mechanical things I just never thought of, even after years of turning wrenches.

I like the one you sent. Let me know how it works for you. I assume unlike my TJ or the 89 F-350 I have, the 85 you are going to try has the square style reservoir?

 

Rectangular cast iron master. But I've just seen a pic of an '86 with a plastic master with a screw-on lid. Will figure out why and if it'll fit before buying the tool. Woukd change the adapter I need.