The stock E39 M5 clutch line starts off as a hard line that runs from the stock master cylinder in the clutch pedal through the firewall.? There it turns into a flexible hose that connects to the hardline for the clutch slave cylinder mounted on the transmission.? The problem is that the flexible hose makes the clutch pedal less responsive and a bit mushy even when brand new, and this phenomenon grows substantially over time as the flexible hose portion wears from engine bay heat. For just about every other BMW model known to mankind, there are aftermarket clutch lines that replace the flexible hose portion of the clutch line with stainless steel braided brake lines.? But not for the E39 M5.? Until now. We start with a brand new stock clutch line and replace the flexible hose portion with stainless braided brake line to which is crimped to a connector that mates with the hard line attached to the clutch slave cylinder.? The line is pressure tested and as durable as any brake line.? And you will notice the difference in the clutch pedal's responsiveness.