rear brake leak

[04silverprix]

Anybody ever experience a passenger side rear disc brake fluid leak on a 2004 Grand Prix? It's got to be either the brake hose or the caliper. The steel lines seem to be clean.

I plan on filling the master cylinder and see if I can find where the leak is coming from when the pedal is applied. Hopefully it's the brake hose and not the caliper. I've never had a caliper leak before. Usually calipers hang when they become defective.

I have a stream of brake fluid running up the inner wheel well on both ends of the well.

Any thoughts?

 

[BillBoost37]

My thought: Yes, you need to look for the leak. There are no common areas that are prone to leaking.

 

[SlowNA06]

The seals in a caliper can go bad. Wound up replacing the rear one in an '04.

 

[04silverprix]

Yeah it's got to be either the caliper or brake hose. But get this. I filled the master cylinder with fluid and had my wife press the brake pedal while I looked for a leak around the caliper or brake hose. Dry. No leak.
She drove the car this evening and the low brake fluid warning light never came on, the brakes worked fine, etc.
Something isn't right. The fact that I've had to add brake fluid, found fluid on the rear sidewall and on the inside edge of the rim, and on the driveway tells me there's a brake fluid leak someplace. It's a slow leak. I'll check again tomorrow.

 

[BillBoost37]

You let a woman press the pedal. she's not pressing as hard as you would.

 

[SlowNA06]

Might also be something to do with the operating temperature of the fluid.

 

[04silverprix]

You know that's interesting that you bring up the temperature of the brake fluid. It's been extremely hot around here and maybe that could have something to do with it.

This leak is intermittent. I filled the master cylinder yesterday and so far the pedal is normal and the warning light has stayed off. But we all know car problems don't get fixed all by itself. I plan on removing the wheel again to see if there's any fluid on the back of the tire/wheel or anyplace else. I should also remove the caliper and see if I can find any brake fluid. Maybe then I will find the trail of the leak.