Metal lines and rubber brake hoses should be inspected regularly for leaks and exterior damage, because metal lines can be easily crushed and kinked beneath the vehicle, which will limit the flow of fluid and affect braking. Rubber hoses should be inspected for cracking or scraping as such damage can cause weak spots which can fail under pressure. When lines are removed or disconnected, extreme cleanliness is essential; all of the joints and connections should be cleaned prior to disassembly and lines and ports should be plugged after opening. Note: New lines and hoses should be flushed with brake fluid before installation to avoid contamination. To remove a line or hose, disconnect the negative battery cable, jack up and support the vehicle, and eliminate as many wheel and tire assemblies as necessary for accessibility. Clean the area around the joints, place a catch pan underneath, and to disconnect the hose or line use two wrenches to dissociate the connection, paying attention to use a back-up wrench so as not to damage the fittings. Disconnect any retaining clips or brackets and take the line off, being careful to tape or plug any remaining clips and ports if the brake system is going to be open for an extended period of time. For installation, begin your new line or hose at the end that is furthest away from the master cylinder, having both of your fittings well-threaded and not rubbing to any other part, with 1/2 inch minimum space from the steering column and moving parts. Reinstall any protective shielding or insulators, tighten any fitting using two wrenches and reinstall any retaining clips or brackets. If applicable, reinstall the wheel and tire assemblies, lower the vehicle, refill the brake master cylinder reservoir with clean brake fluid that meets DOT 3 specifications, properly bleed the brake system and reconnect the negative battery cable.