Firstgens.com

67 power 4 wheel disc. Parts store told me to use Dot 4. Cover on master cylinder says use only Dot 3. Which do I use?

I'd go with what the company that put together the Disc conversion recomends. Back in the day Dot 4 was for British cars , something about the rubber wasn't compatible with DOT 3. I'm not sure if any of that technology has changed in 50 years or not. I put DOT 5 Silicone in mine in the mid eighties. I'm looking forward to see what all the seals and cylinders look like after some of what I've heard thru the years about Dot 5.

Jeff

Use the dot4 synthetic. I used valvoline dot4 synthetic in mine. So far so good.

DONE!