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2012 Boss 302 seized brakes

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Hello, everyone. I let my 2012 Boss 302 sit for an extended period of time and now it is locked in place because the front Brembos appear to be seized. I have seen various videos saying they need to be replaced or rebuilt. Just wanted to check with the experts here for advice. Thanks in advance.
 

carver

breaker of wrenches
445
598
ontario
I wouldn't say I'm an expert....but I do park my Boss indoors each winter for up to 6 months ( in the winter). If I don't rock the car forward and back every so often the pads can stick to the rotor. Plus I leave the hand brake off. I have never had the calipers seize. If you give it a little gas it might let go. Don't put the car thru the garage wall...Hahaha! :oops:
Is your Boss indoors?
 
Boss has been indoors for the long NY winter. Just came back inside from jacking the car up. Front right was stuck so, being me, I forced it to move and the disc is super pitted and scratched and still gets stuck. Will need to replace the disc's for sure.
 

carver

breaker of wrenches
445
598
ontario
Boss has been indoors for the long NY winter. Just came back inside from jacking the car up. Front right was stuck so, being me, I forced it to move and the disc is super pitted and scratched and still gets stuck. Will need to replace the disc's for sure.
Make sure the caliper's are sliding freely on the pins and pistons not seized . Something else to check... I have had 2 cars with flex hoses collapse ( one front and one rear ). That means you can force fluid to the brakes when you push the pedal but they don't release. Very frustrating !! 😫
 
Make sure the caliper's are sliding freely on the pins and pistons not seized . Something else to check... I have had 2 cars with flex hoses collapse ( one front and one rear ). That means you can force fluid to the brakes when you push the pedal but they don't release. Very frustrating !! 😫
So on a Brembo car, the front calipers are fixed so there are no slides. And on all cars, none of the brake pistons are extended/clamped hydraulically when parked. If you leave the parking brake on, the rear pistons would be mechanically actuated.

So, if the parking brake was not on, look somewhere else for your issue. Your calipers *could* have failed over the winter, but that would be a seal failure and a low/no pedal type of thing.

If the brake was on, check cabling for the parking brake and the rear calipers. In my experience, those slides are more troublesome.

And define "stuck in place"? It won't move under engine power? Or can't be pushed? Not being able to turn a wheel by hand when jacked up is not great, but not a super good indicator. It would not be unusual for a sitting car to have the rotors rust as you describe over a period of time (some cars do it overnight) and feel slightly stuck. If it would move under its own power and you have a brake pedal, I'd drive it gently and see what happens. You are not going to have a complete brake fallure here. 99.99% chance the rust unfreezes and the rotors clean up and everyone moves along.

DaveW
 
6,361
8,184
FWIW clutches do the same thing, they will stick to the flywheel in humid conditions and you have the " break" them loose after sitting. As an example, I almost launched an American LaFrance pumper through the station bay doors after we ran it in flooded conditions several hours before. Clutch was fully in when I hit the starter button(s)
 

carver

breaker of wrenches
445
598
ontario
FWIW clutches do the same thing, they will stick to the flywheel in humid conditions and you have the " break" them loose after sitting. As an example, I almost launched an American LaFrance pumper through the station bay doors after we ran it in flooded conditions several hours before. Clutch was fully in when I hit the starter button(s)
Now that's funny !! LOL but probably not at the time.
 
DaveW you are right that I can drive the car and I do have solid braking power. It was where the car could not be pushed and the right front brake would make it so I could not turn the wheel when up in the air. When I brake there is a lot of vibration. I will change the rotors this week and look at the pads as well. Appreciate the responses thanks.
 

TMSBOSS

Spending my pension on car parts and track fees.
7,529
5,245
Exp. Type
HPDE
Exp. Level
10-20 Years
Illinois
I restored a Maxton Rollerskate.
..Yes, its a car.
When I went to the storage container it had been in for years, one wheel would not turn. I took a Brass drift pin 12" long and put it against the brake and "Tapped" on it with a 2lbs hammer. The shoes came loose and the car rolled.
This should get the brake freed up if its a stuck pad.
 

Dave_W

Cones - not just for ice cream
984
1,277
Exp. Type
Autocross
Exp. Level
20+ Years
Connecticut
I will change the rotors this week and look at the pads as well.
Sounds like the one or more pads stuck to the rotor while sitting. You'll get a vibration under braking because the area of the rotor where the pad was stuck now has a different level of friction material deposit than the rest of the rotor.

You can drive with them like they are, and eventually they'll get better. Or you can take the rotors off, hit them with a coarse Scothbrite pad or superfine sandpaper (like 600+ grit) and some brake cleaner to scuff off the current friction material transfer layer, remount, and go through the pad bedding process again. That should get everything back to normal.
 

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