Brake Fluid

[GCDingo]

I am thinking of "changing" my brake fluid for a refresh with a lazy attitude to not draining the brake lines (hence bleeding), have 2015 limited diesel never changed since new with 125k km and manual says Dot 3 but Dot 4 compatible. Can I just syringe out the dot 3 from reservoir and top up with dot 4? Was just thinking a couple of dilution changes over time. I was just going to use this.
https://penriteoil.com.au/assets/pis...20FLUID%20.pdf

[OLMATE]

Better than nothing, only thing is it's like the power steering reservoir, using a syringe only replaces whats in the reservoir, saying that! any contaminants, moisture in the caliper pistons will remain and not be flushed out/ replaced, no matter how many times the reservoir is replaced

[drover]

Be a waste of money and you won't achieve anything as the new fluid will just absorb any moisture from the old stuff and you won't change very much as the brake fluid doesn't flow as such and you will still have the old stuff in the lines, you need to change the fluid by bleeding, in the correct manner so the system is flushed, not only fluid is changed but any particles get flushed out as well.... Just sucking a bit of fluid from the reservoir won't get the crud laying down amongst the valves as OLMATE said.

If you are unfamiliar with the process just get a brake shop to do it, not a local spanner shop, care does need to be taken as getting air in the system can stuff up the ABS unit ..............

[Classic Boy]

A simple method is to syringe the reservoir and refill with new dot 3or 4 fluid then open the bleeder at the wheel furtherest from the master cylinder let gravity drain the old fluid from the lines until it comes through clean keep topping up the master as necessary. Repeat on the next furtherest until the closest wheel last, do one wheel at a time and don’t let the reservoir get totally empty.
If done this way you replace nearly all the fluid and no need to pump the pedal at all. On older cars it is done this way to keep the system clean but deliberately not push the master cylinder piston seals into the normally unused areas of the cylinder which can risk nicking or otherwise damage the seal over any accumulated debris.

[OLMATE]

One of these will do the trick. Slips over the bleed nipple and draws all the old shit out, whilst keeping the master cyl topped up.

https://www.ebay.com.au/itm/39489953...oAAOSws7tlEBcN

[drover]

Originally Posted by OLMATE

One of these will do the trick. Slips over the bleed nipple and draws all the old shit out, whilst keeping the master cyl topped up.

https://www.ebay.com.au/itm/39489953...oAAOSws7tlEBcN

I wonder how well it would go or be a one timer certainly make life easier...... still have to keep a close on the reservour.



If we are going to go into the How..........
Then I always use a bit of plastic tube which fits over the bleed nipple and runs into a clear container, I found a Vegemite jar with a hole in the lid to fit the tube means it doesn't come out, the jar has enough fluid in it so air isn't sucked back up the line, then with someone to pump the peddle about 3 times, they then hold it down, while you open the bleed nipple for the fluid to flow for a second or so, then close nipple and allow the peddle pusher to pump it up again, checking the reservour every couple of pumps, when the fluid comes clear move to the next one .... the pedal is not to be moved whilst bleed valve open..... this is started from the furthest bleed valve then the next one, with ABS systems fitted the utmost care must be taken to ensure the reservour never gets low and air doesn't get into the system or youve stuffed it.... unlike the old stuff where if you got into the system you just had to bleed away till you got it out..................
Its when you change very worn pads/shoes that you can get into problems with pistons leaking as they can have a build up around them, I will pull back the boot and wipe the piston down before pushing it back in, this usually sorts and later leaking.

[Jeeper6]

I upgraded the calipers on my old WJ Overland from Teves to Akebono to stop the warping effect the crappy Teves calipers had on the discs.
I used the same method as drover mentions above...when I disconnected the line from the Teves calipers I connected immediately to the Akebonos as the lines dripped to as not to allow air in...then connected a tube from the bleed screws in to a jar and pumped away keeping reservoir full.Never had a problem with the ABS function...