As I have mentioned on this forum in the past I only replaced the o-rings and not the entire plastic lines. I don't remember the dimensions, but what I did was to take samples of the existing o-rings with me to Lowes and Ace Hardware and I was able to find replacements there. The replacements were slightly thicker so it took a lot of effort to reinstall the lines, but I did it and the system is still leak-free to this day (it's probably been about a year).

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2004 VW Jetta TDI (manual)

Past MB's: '96 E300D, '83 240D, '82 300D, '87 300D, '87 420SEL