Problem with the brakes?

2013 Mustang GT V8. I have a strange problem with the brakes on the front passenger side.

I had my car on the lift a few weeks ago to diagnose a scraping noise I heard while turning left at slow speeds that was coming from the front passenger side.

Mechanic said all suspension components looked fine, the only thing he could find was the front passenger side wheel had noticeably more resistance when trying to spin it by hand while on the lift. The front drivers side spun easily and freely when pushed by hand while on the lift but the passenger side did not. It requires a bit of force to make it spin and it does not spin freely (it feels like brake pads are dragging on rotor - I’m not sure (and even doubt) this is the problem, however it’s the best way I can describe how it feels.

Mechanic said the front passenger caliper did have a small leak from the piston and said it was likely the pistons were not retracting all the way causing the pads to drag on the rotor when driving hence the wheel not spinning freely while on the lift. He recommended replacing the caliper.

Well today I replaced all of the calipers just for good measure since my car has over 100k miles and all is well, brakes feel good… except the front passenger wheel still has resistance when trying to turn it freely in the air. The drivers side still spins completely freely.

Not sure if this is worth noting but the front passenger wheel DID spin freely when the wheel AND caliper were off (it spin freely by hand with just the rotor and pads on) which tells me the pads scraping the rotor are probably not the problem.

Please help me

Change your rubber brake hoses. All of them. The pass front is failing but the rest are not far behind.


Just visually inspecting the hoses they all looked fine. No visible damage or leaks and on the outside they all look to be in good condition.

I was bleeding the brakes using a bottle bleeder since I replaced the calipers and I saw clear brake fluid flowing through the clear bottle hose on the passenger side when I bled that brake line. So doesn’t this mean the front passenger line is properly flowing the fluid to the caliper?

You can’t see or feel bad brake hoses. When they go bad they act like check valves to reverse flow. The look fine, bleed great but are failing anyway.


Do the test again.

This time, crack open the bleeder screw.

If fluid squirts out and the tire now rotates freely, the car needs brake hoses.



Just wondering how would rear brake hoses failing be diagnosed? Since the rear wheels can’t be spun by hand

Drive 20 miles. Stop and touch each wheel. The hot wheel has a failing brake hose. Crack the bleed screw on that wheel as tester said and fluid will squirt out. The wheel with a good brake hose won’t do that and the wheel will be cool.

Trust me when I say if one goes bad, change them all. A new hose is cheaper than replacing the bad one and then replacing a new.caliper and the pad when they burn up…4 times.


Is the drag even or are there tight and free spots during rotation?

Drag is even

Is it safe to say I 100% (through process of elimination) need new brake hoses? Since I already replaced calipers rotors and pads all around and also bled the brakes and the front passenger wheels still dragging?

I don’t want to open the bleeder screw if I don’t have to because then i’ll have to bleed all the brakes again to get it to a shop and will have to bring all my tools, jack and jackstands from my apartment to parking lot and lift everything up again and I don’t want to unless I HAVE to to get a proper diagnosis.

When brake hoses deteriorate, the rubber inside of the brake hose separates from the hose structure. This separated rubber acts like a check valve.

That is, it allows hydraulic pressure to be applied in one direction, but not release in the opposite direction. So, the brake remains applied until the hydraulic pressure is released thru the bleeder valve.


1 Like

How do I know it’s the braided brake line that connects to the banjo bolt that’s gone bad or if it’s the entire line that connects up to the master cylinder that needs replacing when I search for “2013 mustang gt brake lines” it only shows results for the lines that are about 6 inches- a foot long that connect to the banjo bolt, not the long plastic lines that connect to the master cylinder? Or do those ones not really get clogged/go bad?

I’m talking the brake hoses to the brake calipers.

These are the hoses that get flexed all the time and are prone to breaking down inside.


1 Like

These ones right?

Those aren’t stock brake hoses.

So, I don’t know their construction.

But I see they come with a 3 year warranty.

So, you got that going for ya.


Do you think I’m fine to drive for a week or so with the bad brake line until the parts come/I have time to fix it?

Brakes work fine and no fluid leaks - I was more worried about ruining the brand new front passenger caliper due to the bad brake line that’s causing it to stick.

Do you think driving for a week like this will damage the caliper / pads?

If there’s a brake hose that isn’t allowing the caliper to fully release, distance and speed will dictate how quickly the pads and rotor burn up on that wheel.


You could always go to your local parts house and buy a brake hose for $20-$30 and use it until the good stuff comes in, much cheaper than overheating the pads, rotor and possible new caliper, as long as you don’t let the master cylinder run empty you should only have to do a quick bleed on that one wheel…

You could also take it to a mechanic and let them fix it, probably that day…

I know it’s more “expensive”, but it would solve the problem. It sounds like you have the skills to do it yourself…but there’s also a cost in your time and things of that nature.

Given your hoses are 11 years old, and given that you have symptoms that they’re internally breaking down, if it were my car, I’d replace the hoses immediately.

I’ve seen too many of them fail. And yes, they fail internally.

1 Like