Black Fluid Inside Barrel of Front Wheels (pic)

[stash3630]

I use my ST for Rallycross. When I swapped my wheels back at my most recent event, I noticed that there was a lot of black fluid or oil sprayed all over the inside barrel of the front wheels. There’s so much dirt and mud in there that I can’t really tell what it is or where it’s coming from.

I figure it’s brake fluid or power steering fluid. But the fact that it's symmetrically inside BOTH wheels makes me think it's NOT brake fluid. Under the hood it looks like there’s been some seepage or spray from the brake fluid filler cap; although it could've been like that before.

I put hawk pads in there in the fall and the amount of brake dust and squeal is like nothing I’ve ever seen or heard. So to combat that, I went back in and greased the anti rattle clips a ton and that helped the noise a LOT. But maybe I got overzealous with the grease/paste and it's mixing with the brake dust creating this black fluid? That greasing job was a while back though so I feel like I would’ve noticed the back fluid spray before now, but I digress.

Maybe it’s cv boot grease? It’s such a mess of baked on mud I can’t really tell, but there is definitely a lot of black stuff all over the inside barrel of the wheels.
I recently had my shop put in steel braided lines and do a full fluid flush so maybe that's a factor?

Car is performing great and braking normally. Any ideas?

 

[Capri to ST]

Just to eliminate one possible cause, it's not power steering fluid. We have an electric power steering system, there's no hydraulic fluid.

 

[stash3630]

Thanks @Capri to ST !

 

[stash3630]

I'm leaning to CV boot grease

 

[M-Sport fan]

I'm leaning to CV boot grease

Yeah, sadly that's exactly my first thought as well, as it's real easy to tear the boots open when the CV joints are working at the extreme vertical wheel travel angles caused by Rallycross, or stage rallies.

I forgot from your other posts, are those Braid Acropolis wheels with ARA competitor 'take off' gravel Pirellis (or did you buy the tires new?)?

 

[Capri to ST]

Thanks @Capri to ST !

You're welcome, good luck figuring out what it is. Let us know when you do.

 

[Erick_V]

Looks like axle boot grease? I had a boot with a small hole in it but don't recall the color of it, but I remember it being all over the barrel like yours is

 

[stash3630]

I forgot from your other posts, are those Braid Acropolis wheels with ARA competitor 'take off' gravel Pirellis (or did you buy the tires new?)?

I sold those 16” Braid Winrace N Lars to a fellow forum member on here and they look fantastic on his black ST!

And yes! I’m running ARA takeoff Pirellis on some 15” Braid Fullrace TAs on my car.