Brake Hose Anatomy...

[cn90]

- My 2004 V70 with 105K miles, the FRONT Brake Hoses x2 were cracked. All of you should check yours and replace them.

- I used ONLY ATE brake hoses.

- So...I used a dremel to cut the crimp to see the anatomy. Anyway, this is no different than washing machine hose or garden hose. Basically the rubber hose goes in and the hydraulic machine does the crimping part.

- I also include some fittings I found on the web...

Brake-Hose-01.jpg (354.35 KiB) Viewed 963 times

Brake-Hose-02.jpg (415.28 KiB) Viewed 963 times

Brake-Hose-03.jpg (19.88 KiB) Viewed 963 times

[mrbrian200]

Brake hoses on older domestic cars through the MY-90s I've seen fail were different: is the not crimped end fittings that have changed, but the actual hoses.
There's still an inner thin wall hose that carries the fluid. What has changed is the reinforcement around it. Older (and newer/lesser?) hoses use a a steel flexible conduit around the center fluid passage as the reinforcement. These OE Volvo hoses replace the steel with what looks to be some sort of braided aramid or PVA reinforcement. On the vehicles I've seen at the yards with a cracked outer rubber layer this type of reinforcing material does not appear to be affected by road salt and corrosion. The steel reinforced hoses are sensitive to the elements big time. On the steel reinforced hoses, once the outer jacket cracks it's a relatively short matter of time until the steel reinforcement succumbs to rust and corrosion. The inner fluid passage (usually EPDM) cannot hold pressure once the reinforcement fails.
Hence, I'm not sure a cracked outer layer on these Volvo hoses is quite the detrimental situation that we think it is - because the reinforcement itself is made of a corrosion resistant material that appears to be quite immune to road salt that would, once exposed, take out a steel reinforced hose in short order.

I do understand that the regulatory standards for brake hoses, FMVSS 106, defines a minimum standard with regard to working pressure and durability/resistance to corrosion. As FMVSS 106 does not specify any specific material construction, OEs and aftermarket are perfectly free to alter designs to exceed those standards.

Are these aramid reinforced hoses known for 'popping open' once the outer rubber jacket degrades like the steel reinforced hoses are known for?

[oragex]

Nice post. Would loved to see a close up of the damaged section.

Both front on mine (2003 with 100k miles too at that time) were cracked quite severely at the same place. Rear ones have slight cracks, nothing too worrying.

Can't say enough how unpleasant is to start screwing these new hoses at the caliper: the fine threads just don't want to 'catch' while the brake fluid reservoir is emptying.

Got my hoses from NAPA (brand?), still good about 5 years later.

[cn90]

Yeah,

- I only use ATE hoses.

- The TRICK to minimize fluid loss
- Use vice-grips to clamp the OLD hose to stop losing fluid, then cut the OLD hose.
- Undo the part of OLD hose that goes in the caliper.
- Install new hose in the caliper.
- Now undo the OLD hose at the bracket (I sprayed lubricant one week ahead of time). You will lose a bit of fluid.
- Screw in NEW hose at the bracket.

[jonesg]

Yeah,

- I only use ATE hoses.

- The TRICK to minimize fluid loss
- Use vice-grips to clamp the OLD hose to stop losing fluid, then cut the OLD hose.
- Undo the part of OLD hose that goes in the caliper.
- Install new hose in the caliper.
- Now undo the OLD hose at the bracket (I sprayed lubricant one week ahead of time). You will lose a bit of fluid.
- Screw in NEW hose at the bracket.

also, remove reservoir cap, add small peice of saran over the opening and replace cap.

[abscate]

If you start the hose before you put the caliper back on, you can feel the threads engage by having the hose in a relaxed position with respect to the caliper. Screw it in until it bottoms, install caliper, then another 1/8 nip to tighten.

Thats exactly 31.4159 Newton Meters