I was looking for a black 2K primer high-build surfacer for use under semi-gloss black and found very few products on the market.
Yeah, you can buy black 2K sealers, but there is a dearth of high-build surfacers in black.
The reason for black is obvious -- if you get a chip or ding and you have used gray surfacer you will see gray. And you need high-build due to the age of our cars and the rust pits that develop.
So I gave SpeedoKote high-build a try and I am impressed (pic 1).
If you mix it one way, it's a sealer. Mix it with more reducer and it becomes high-build. Weird.
But it seems to work. After letting it dry it gets hard, unlike most surfacers which sand very, very easily. But it will sand with 180 well enough. It also fills pits like nobody's business.
My rear brake drum backing plates has some issues with pitting. My rear axle housing is even worse. As a test -- and since my housing needs to be media blasted -- I started with the backing plates . Rusty and pitted in a number of places (pic 2). And glass bead blasted in the same pic.
First sanding in pic 3.
Second coat, not sanded yet (pic 4), with numbers taped over so they don't get filled and will get painted with final semi-gloss.
It's $39/quart with catalyst through Amazon.
Edit for clarity