Is it a good idea to flush brake fluid?

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Anyone ever have a problem after flushing brake fluid?

My mechanic - a real pro, said messing with a flush /fluid replacement and or blead will give you all sorts of problems since you force the dirt thru the system, clogging lines, calipers, blowing master cylinders.

Anyone seen issues arise after a flush?

I would like to improve the pedal feel yet on the side of caution would like to see what other have experienced specific to the LX450 or 80.

brakes, rotors, pads all new
 
I haven't had any problems related to flushing. I flushed mine when I swapped the master cylinder. Most of the fluid in the lines was almost black (probably original), so I think I did my brake components a favor by getting all that junk out of there.
 
I've never had a problem or heard of a problem flushing the fluid. I would however suck most of the the old fluid out of the reservoir and top it off with fresh fluid before bleeding the the system to minimize introduction of new crud into the master cyl.
 
I've never had a problem or heard of a problem flushing the fluid. I would however suck most of the the old fluid out of the reservoir and top it off with fresh fluid before bleeding the the system to minimize introduction of new crud into the master cyl.

I recently replaced all of the brake fluid in my truck without any issues and my old fluid was dirty as well. I sucked all of the fluid out of the reservoir first and put fresh in before starting. Buy a large bottle of brake fluid because you will need all of it. Don't forget to bleed the load leveling brake bias valve(?) on the rear axle as well. Keep the reservoir topped off and start at the furthest point and bleed each until you get clean fluid.
 
Ideally, brake fluid should be flushed every couple of years.
Typically it is not.:hillbilly:

Depending on the relative humidity of your area, the fluid should be flushed more or less frequently, because brake fluid is designed to absorb moisture, in order to keep internal parts from rusting.

As the ratio of H2O increases over time, rust increases along with it.

Usually, the darkening color of the fluid is an indication of oxidation.

So the rule of thumb is...keep your fluid light colored.

If the brake system has been neglected for many years, as most are, any proficient professional mechanic will attempt to protect themselves from liability:hillbilly: by warning the owner of a neglected system that it could be problematic to open up their system, if there's a quarter inch of mud in the bottom of their reservoir.:D

Nevertheless, it is worth it to flush, flush, and re-flush the system until it runs clean, in order to get all the tiny particulate matter out of the system.

When I worked for a large general contractor, with hundreds of pieces of equipment, some of them that were infrequently used had pretty dicey brake systems on them.

I would use a gallon or two of fluid (cheap in the long run) and open the wheel closest to the master, first.

I would re-circulate it until it ran clear, filtering the fluid with an in-line fuel filter, before returning it to the reservoir.

Move to the 2nd closest brake cylinder next, open the bleeder valve, and flush it.

After doing the same to the 3rd and 4th, then go back Jack, and do it again.:D

This will get only 90% of the old brake fluid out. The rest is in the slave cylinders, and the second time thru, I pump the brake pedal, to get the slaves flushed.

This method is only for badly neglected systems, and there's no reason to go to such lengths, if your system is flushed regularly.
HTH:steer:
 
The danger is that pumping the pedal to the floor during a regular 2 person bleed can destroy an old brake master.

Using a pressure or vacuum bleeder could prevent that.

We flush brakes all the time.
 
One thing I have found useful for flushing the break system it ATE super blue brake fluid. It is DOT 5.1 fluid but instead of the usual amber color it is blue. Every flush I move between ATE amber and ATE blue, so I know that when I see the color change at the bleeder I have more or less flushed that line. I do this every year on my motorcycles, and a little less frequently on the cars and trucks.

http://www.europaparts.com/ate-supe...tore=default&gclid=CMvU-bqGgLQCFao7MgodK00Aaw

(the call it DOT4 but technically it exceeds the boiling point of DOT5.1 so it is DOT5.1 in every way except the color.)

Geof
 
I can't imagine your experienced pro being against brake fluid changeouts. What I think is happening here is you misstated what he and you spoke of. A common problem is shops using pressure flushes through transmissions and loosening things that end up in delicate trans valves, etc. So you must have been speaking of that and other car maintenance items like brakes, oil, etc, and related it here as brakes.

Or, possibly he was speaking of some system that uses power flushing on brake systems which he'd also be wise to be against.

So, your guy is probably accidentally being misrepresented here. And some excellent brake procedures posted above as well. Every brake system has a sequence of what to flush first in its service manual worth knowing about. The 80 series indeed has a 5th brake bleeder on the LSPV and it also has a specific sequence your tech should be aware of.

DougM
 
It's just like every other fluid in your vehicle. It gets old and for proper maintenance, should be replaced over time. Keeps things running and lubed at it's best. More so in an older vehicle.

I too would recommend switching to a higher-temp brake fluid such as the ATE Blue listed above. Yes, it is a bit more, but personally, I like to have every advantage I could possibly have when stopping. Our rigs are heavy. In certain environments, brake fluid get's pushed to the limit (it boils). When you reach that limit, you have "brake fade" (a mushy pedal at full force), which is NOT a great feeling. A higher temp fluid such as the blue won't boil as quick. It's why race vehicles use it (and sometime police agencies due to pursuits).
 

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