Changed the oil and fuel filters in an 08 F250 today, after I got done had no brake pressure (fluid reservoir was still full), just wondering if anyone else has ever run into this??? Trying to figure out what is up with it.

 

Is the pedal hard or does it squish easily the whole way down?

 

It's squishy, like there is no boost. Also, opened up the brake fluid reservoir and it looked like it was filled with transmission fluid? I know I use tranny fluid as power steering fluid but didn't think you could use it as brake fluid. I think it may have a hole in a brake line but not sure, any ideas?

 

Tranny fluid does not belong in the master cylinder. I've never heard of that before.

 

Yeeeaaaaah after doing a little further research, I don't know what idiot put that in there, it will ruin the master cylinder. I guess I was just the lucky guy who got it in when it decided to go out....luckily the customer was someone I have been dealing with for a long time and didn't blame me for it.

 

Ah yes. It does something strange to the seals in the brake system. I tried that once when I was in a pinch with my 83 Ranger. It was very low so I thought ATF can't hurt...boy was I wrong! Drove home with pretty near no clutch.

On edit...I added ATF to the clutch system which is designed to use brake fluid. Sorry for making myself so clear!

 

Sounds kinda like the deal here on the 150s

https://www.ford-trucks.com/articles...brake-failure/