Toyota Tundra Forums banner

1 - 15 of 15 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
I have a brake fluid leak and I can’t find where. I had it in the shop and they did see anything. I have to add every week. I don’t see any leaks hoses all look good. I have added a lot of fluid so far where else should I be looking?
 

·
Registered
Joined
·
3,286 Posts
I had a leak years ago and the fluid looked like it was coming out of the middle of the floor pan no where near any brake likes. It took about an hour but I finally figured it out. It was a tiny pin hole in one of the lines 4 feet away. The hole was so small I could not find it until I realized I needed to have the car on to build pressure in the system and see it shoot out. Point is you could be in the same boat where its a tiny leak and its not going to leave a massive puddle and make it easy for you to see. Turn the truck on, get underneath and have someone inside just keep pumping away at the brakes till you either see or hear the leak. If you dont have anyone that can help get an old bed sheet and lay it out flat under the whole truck if you have one big enough. Get in and pump the brakes, go under and keep checking for leaks. The fluid should show up on the sheet.
And it could also be leaking by the actuator or down the firewall under the master cylinder so check there as well.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #3
I have done that as much as I can with the snow here, didn’t see anything shooting out. I had some one pump the brakes and looked around. The pedal stays up as well.
 

·
Registered
Joined
·
5 Posts
Could you possibly have a leak around the plastic fluid reservoir on the master cylinder ? Loose or defective cap ?
A crack in the plastic , or a bad seal where it mates to the master cylinder ?

Possibly a loose or defective bleeder screw ?
And you can always check wheel cylinders for leaks .

Good Luck .
 

·
Registered
Joined
·
5 Posts
I have a brake fluid leak and I can’t find where. I had it in the shop and they did see anything. I have to add every week. I don’t see any leaks hoses all look good. I have added a lot of fluid so far where else should I be looking?
If you have to add fluid every week and the "shop" couldn't find the leak - you need to find a different shop. Agree with the above though - it's likely leaking into the brake booster. You'll likely need a new master cylinder.
 

·
Registered
Joined
·
2 Posts
I have a brake fluid leak and I can’t find where. I had it in the shop and they did see anything. I have to add every week. I don’t see any leaks hoses all look good. I have added a lot of fluid so far where else should I be looking?
I had this same problem a year and a half ago. It was the brake booster in my case. I ended up replacing the master cylinder/booster assembly ($$). If this is your problem, you will likely see puffs of very white smoke from the exhaust, especially on startup.

At any rate, something to consider.

Enz
 

·
Registered
Joined
·
3,286 Posts
How does brake fluid make its way into the engine and come out the exhaust?
 

·
Registered
Joined
·
23 Posts
How does brake fluid make its way into the engine and come out the exhaust?
Brake boosters are vacuum operated, so on startup a high vacuum is pulled near instantaneously [the motor is basically a very powerful air compressor], more than enough to suck some brake fluid that's leaked into the booster through the one way valve into the intake.

Anyway, forgot to mention pulling the booster's vacuum hose off to see if there's any fluid on/in it to confirm for sure this is the problem as even just pulling vapor from a minor leak will leave some residue.
 

·
Registered
Joined
·
151 Posts
I've been having brake problems and fluid loss. Haven't driven it lately. Started it up and tried the brakes and got the white smoke !! Lots ! I already had the master cylinder. Ordered the booster.
When I'm done with that, the only brake thing that won't have been replaced in the last 500 miles is the lines....oh and the proportioning valve,
 
1 - 15 of 15 Posts
Top