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There is a thread on the chemical composition of PTFE tape (Teflon tape) here: Master cylinder leak but my question is, will PTFE tape stand up to the heat generated by front disc brakes? Or, will the heat generated melt it and just make a messy goop that no longer really seals?

EDIT: Applying a little Google-foo to the problem turned up this:

[PTFE is a white solid at room temperature, with a density of about 2.2 g/cm³. According to DuPont its melting point is 327 °C (620.6 °F), but its properties degrade above 260 °C (500 °F).

So the question can be refined to is that high enough to avoid problems with front disc brakes? Since the tire begins to soften to the point of not working well at roughly 160 to 170 deg C (320 to 338 deg F) it should be fine.

Does this match what folks have seen or tested in the real world? Is there a downside to using PTFE tape on brake bleeders, like bits of the tape getting into the brake line?

(The quote comes from here: https://answers.yahoo.com/question/index?qid=20070824070354AAUaCbi )

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cdunn
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Two points;

  1. Teflon tape is not a sealant. It lubricates the threads, so that you can insert the threaded part deeper, and as a side-effect it fills small gaps - but it was never designed as a sealant.

  2. Brake fluid dissolves/degrades PTFE. Try Permatex instead, if you want to go this route.

  3. If you think you need a seal, you should fix the problem rather than putting a band-aid on it.

If you still want to use PTFE still, then buy the good stuff (it's usually grey in color), rather than the 50c white stuff at the big box hardware store - a tip for plumbing as well as car repairs!

PeteCon
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TBH I've never seen teflon tape on brake bleeder screws or any brake line fittings.

It seems kind of stupid to try especially in a professional environment where you're open to litigation and possibly criminal charges if the tape fails and someone dies.

Ben
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