Clutch fluid is always dirty

Just coming on here to see if anyone’s had similar issues. Ive replaced my master cylinder, my clutch slave, and the soft line on my 99 Tacoma and my fluid is already black at just after only a week of driving. No leaks it’s at the same level but it’s basically black already. Only thing left is the handlines, is it typical to have to to replace these? I’m only at 160k miles but I guess thats a lot for any vehicle. Any advice is appreciated

 

Think that black is all the seal material from worn MC and some from inside of the rubber line you RR’d

think if your rebleed system fluid will look fine

as far as the hard lines, if you want to go crazy can blow them out with brake clean/compressed air…..but think tht is over kill
Let everyone know!

 

Oh yeah
That’s a reason I try to bench bleed clutch/brake MC’s b4 installing

 

Yea I mean fluid looked perfect after I was done bleeding and I was bleeding it like crazy. Theres something that’s creating the black deposit, it almost looks like metal. I really did bleed it like crazy tho and the fluid was clear for about 3 days before I went on a pretty big off-road trip

 

Just what brand parts did you purchase ?
Over the years using off brand I had failures in under a 1000 miles.

Poor manufacturing causing premature wear ?
I have hard lines with over 200,000 miles with no fluid discoloring.

 

I used all aisin oem parts that looked great when I inspected them before installing and still look good now just full of bad fluid

 

By chance has your firewall cracked where the clutch bracket attaches??
Shifting how the rod penetrates the Master Cylinder?

 

Sorry what clutch bracket do you mean?

 

I mean I took everything apart bench bled both the master and slave, flushed the lines like crazy, cleaned them with throttle body cleaner and blew it all out with compressed air. Still went back to dirty after a week. I also vacuum bled it for like 30 minutes, it was real dark at first but I was certain we got it all out by like the 4th bottle of clear brake fluid

 

We've had to repair many ford rangers of this issue back in the day...
PIA...

 

My truck is low mileage and in immaculate condition, no cracks on the firewall

 

Where the brake pedal attaches to the "firewall" of the truck..
The wall that separates the engine compartment from the cab.
Have someone pump your clutch pedal & look to see if the area is flexing.
Look from inside & outside.
If the geometry is off, youre re-damaging your new master.

I have no idea if your true is prone to cracked firewall at the clutch pedal / master cylinder area.
It doesnt crack at the pedal.
It cracks where the clutch master cylinder is mounts to the firewall.
constant push of the pedal over years & years puts strain & flex on the metal where the master mounts, & eventually cracks.
Can happen sooner if you have a stiff pressure plate, overtime they can get stiff, requiring more effort to push on the pedal, master, etc...

 

Good call slater

Unk if made for Tacos

but have this on the RSTi
To prevent the exact same condition you described

 

were not saying thats what is, but needs to be looked at!!!

 

Since all your parts are new! Something is breaking down causing things to turn Black. The Cap and The Float are not breaking down ?? Should be easy to see.
You are using the correct Brake Fluid for the Application ??
The wrong Type could discolor quite fast!
Good Luck!

 

Its probably rubber from the flex line. Try replacing it. It's literally the only thing left in the system. Anything floating in the slave is still too far down to get up into the reservoir.

I can't prove it but I'll bet the inside of the brake hose reacts to fresh fluid, and a little bit of coating gets eaten off? You flush it, addd fresh fluid and it eats a little more? I can't think of anywhere else black stuff could come from.

I've seen this too and it is puzzling.

 

It's the rubber lines wearing, the seals and or friction material from the clutch. With Corvettes and Camaros it was a thing/recommended to change the master cylinder fluid frequently.

Turkey baster or syringe the old brake fluid out, wipe with blue shop paper towel and refill reservoir. All manual transmission vehicles would benefit from it.

 

I already replaced the soft line though

 

No I already replaced that

 

No everythint looks fine after it i

Yea I thought that’s what you were talking about. That entire piece looks perfectly fine. Like I said my truck is low mileage and completely rust free. Ive touched pretty much every part of it and all the parts on it have been in great shape as well as everything you mentioned. It all works as it should and is visually completely fine. I do think the problem might lie in the master cylinder though, might just get another one from assin they are pretty cheap but idk