Gravity Bleeding

Wife working all day and the old, black dirty brake fluid has to go. Causing some issues down the line with sticking calipers. Its a mess. Gonna grab some new hoses and new fluid. Gonna have have to do the gravity method for now to bleed since its just me for today.

UPDATE answered my own question. I guess I can ask an alternate…how long does it take to gravity bleed each caliper? Hour?

What are you working on? Gravity bleeding can work on older cars, but if you are working on a newer car with abs it may not work at all.

It takes as much time as it takes, unfortunately. I have cars with ABS that can take an hour or more especially when replacing parts. I usually open one bleed at a time and pump the brake pedal (slowly!) with a hose and bottle attached to hurry it along. It gets the fluid down to the caliper but the final bleed is gravity.

thanks for the replies!

sounds good, sounds like I will be out there a while haha. its all good though, as long as I get that old dirty fluid outta there. the car was inherited from my late grandfather with only 30,000 miles on it, and I assume the fluid was never replaced. even the fuel filter was motorcraft original. slowly getting this thing up and going. oh and its a 96 grand marquis. with abs.

another side question, COULD dirty fluid make a caliper stick? my pax front is sticking a little, hence the reason I wanna go ahead and throw on new hoses and new fluid.

Yes, josh, dirty fluid could (or did) make the caliper stick a bit. Mostly likely it is corrosion caused by moisture in the brake fluid. Just changing it might not work. Try the change first and see. If that doesn’t do it, you could buy a caliper rebuild kit (for 9$ or so) and clean it up with a little emory paper and install new seals or swap for a rebuilt caliper with a warranty.

If the piston is sticking then just new fluid won’t fix it, as said above. I’d plan on either rebuilding or replacing the calipers in pairs.

Have you greased the caliper pins? That will cause them to stick.

Texases has stolen the words right out of my mouth. When the fluid has gotten so bad for so long and has caused caliper issues…The fluid swap at this point will do nothing. The insides of the calipers has already suffered damage to the smooth walls of the piston bore…

You MIGHT get lucky and see a change in performance that was caused by any debris in the lines…but…this is kind of rare. When a caliper begins to bind up…anything SHORT of removing the piston and smoothing out the walls of the caliper bore and the piston will do NADA…

You cant let the fluid get so bad that it affects the calipers…by that time it is more often too late than not. Sorry for the bad news.

But if you go ahead with the gravity bleed…we’d be interested in knowing if it worked out for you. Gravity bleed times vary…so just keep an eye on it…start with the caliper FURTHEST from the reservoir FIRST…then the next one closer… That would be Rear Right, then rear left…front right, front left… I wish you good luck on this one.


I’m siding with knfenimore, the caliper pins are likely the cause, not the pistons. Bleeding the calipers is still a good idea.

Make the changes and keep brake fluid in the MC reservoir at all times. If it doesn’t go dry, then there is less likely an issue with air bubbles. Unplug the ABS module before you start bleeding, before you start work actually. As long as the MC does not go dry, gravity bleeding will not take very long.

Use clear 1/8 vinyl fish tank hose that you can get at the pet department at Walmart pretty cheap. Put a foot or two over the bleed valve, then up over something an inch or more above the bleed valve and then down to a container. Open the bleed valve and let it run until you get clear brake fluid in the vinyl hose.

As long as you keep the MC reservoir full you can do both back brakes together, then both fronts. In theory you could do all four but you would be really busy trying to monitor all four wheels and keep the MC full. I usually do two at a time. The back brakes can take 10 minutes or more, the fronts will be a lot faster.

At some point the brake system will have to bled.

And in order to properly bleed the ABS pump requires a scanner to position the valves. Otherwise you end up with spongy brake pedal.


I was going to suggest something like this
but it appears you have more serious problems.

wow, thanks for all the suggestions and replies. I am going to bleed them tonight, after the rain clears up. Was gonna get it done yesterday but I dont have a garage and at the mercy of the horrible weather in Georgia. Rain and hot. UGH. I need a garage!

In any case, I will unplug the ABS module and bleed them after that. Going to try a brake fluid and hose change first. Cheapest to most expensive option. If that dont work then grab two new calipers for the front and be done with it. Lets hope.

Interesting thing happened though. My master cylinder was slightly over full. I mean hardly enough to really tell. I drained off a bit of it, til its right at the max line, maybe a millimeter below it. Drove it 5 miles, got home. The wheel/brake was not hot. Interesting. Could that have solved the issue? A too full master cylinder? I am a rookie so to speak with brakes, I have only done about 2 brake jobs on both of my cars. The last one went perfect! I know how to do it, just dont know the fine details or how to really dig in there and troubleshoot, so thanks to all of you for your assistance!

Beam me up Scotty.

Select year for details and if I travel at light speed should the muffler bearing rattle any more’’'then rates apply as simple draft or what.?


No, a slightly overfilled reservoir did not cause your calipers to stick.

Provided you have not run the reservoir too low - i.e. provided there isn’t already any air in the ABS module, you should be able to bleed your brakes conventionally without using a scan tool.

For one-man operations I recommend Speed Bleeders. They replace your bleeder screw with one that’s equipped with a spring-loaded ball valve. You crack the screw open as per usual, and then just pump the brakes. The ball valve will open when you step on the pedal, and close again when you let off. This is functionally the same as having someone at the caliper opening and closing the bleeder screw in sync with the pedal pushing. Once done, you tighten the speed bleeders again and move on to the next caliper.

As you have ABS, it’s very important to keep the reservoir from draining too low - once air is introduced up top, you run the risk of air bubbles being introduced into the ABS module, at which point you will need a scan tool to bleed it properly. An easy way to do this is to use something like Mity Vac’s auto-refill kit, which is a bottle that you fill with brake fluid and then stick into the master cylinder. As fluid drains from the reservoir it’s automatically replaced with fresh fluid from the bottle.

If the brake fluid looks that bad, why in the world wouldn’t you bleed the ABS PUMP?

After all, it’s the most expensive component in the brake system.


Brake fluid has been changed and flushed. System has been bled. And those speed bleeders are the ticket, thanks for the suggestion. I took her out on a LONG trip last night, and knock on wood no sticking. Thanks for the tips and advice everyone!

@Tester I would, indirectly. Bleed it, drive it awhile, bleed it again, rinse, repeat. I’m not going to fork over hundreds for a scan tool when the manufacturer could have just stuck a button somewhere that commands the pump to set the valves to bleed mode.


You have to remember that brake fluid in a brake system doesn’t flow. It’s displaced.

The only time brake fluid flows is when a bleeder is opened.

So you can change the brake fluid all you want. But it’s not going to replace the fluid in the ABS pump. That’s why the pump has to be bled so the fluid is replaced.


@Tester Good point, you’re right.

Man I do wish I had a tool to bleed the abs pump. I might take it in for that. Prob be cheaper to have the local guy do it than buy the scan tool. Thanks for the suggestion!