What would happen if antifreeze got put in brake fluid?

SUMMERS918

MEMBER
2002 FORD MUSTANG
V8

So I had the clutch in my car re-done by AAMCO three days ago, just got the car back. Was driving it for the first time yesterday. The brakes started acting weird and sort of making a hissing sound when I pressed them down. So I stopped at the shop next to my house. They thought maybe the brakes just needed to be bled so they did it real quick for me and anti freeze started coming out of the brake lines. We opened the brake fluid reservoir and it was anti freeze. What kind of damage has this done to my car? And how long would someones brakes work if they were tainted with anti freeze? Like Im curious. It had to have just been put in there right? I couldn't have been driving my brakes on anti freeze for a year right?

2 Replies

CJ MEDEVAC

MECHANIC
11,004 POSTS

Greenish or yellowish like antifreeze? maybe not antifreeze! my friend helped me once, by topping me off with power steering this was years ago, and he did tell me that he topped mine off while topping his off he failed to mention "with what" everything inside my system that was made of rubber, that got it on it, kinda swelled up and looked as if it had turned inside out. total system failure was soon to happen, as my front (closest to master) wheel cylinders started swelling ! we were able to flush the lines out. new master cylinder, and 4 wheel cylinder kits.

if whatever was in yours was water based, it definitely would mess you up as far as braking. ever notice when bleeding brakes, the brake juice will just wash off your concrete. it's water soluble, i really think that if you thoroughly flush the master cylinder and lines they will be ok. i would definitely remove brake calipers, and slosh them around with brake fluid and blow them out with air.

Here is a guide

https://www.2carpros.com/articles/brake-caliper-replacement

the medic