I have a C5 with power brakes (wet brakes) that is leaking hydraulic fluid from behind the left front wheel. One tech stateed that he previously replaced the O-rings on the brake lines because they were blown out. Another tech thinks the brake housing/case could be cracked. And another tech stated that the axle could be leaking.

The truck leaks very slowly when sitting.
The truck leaks pretty bad when driving.
The brake pedal feels firm and consistent.
The brake housing doesn't appear to be leaking/cracked.
It seems to leak worse with the activation/deactivation of the parking brake.

I'm open to suggestions on what you folks may think the issue is before I start disassembly. I don't have any technical resources for this brand or model so any assistance would be greatly appreciated.