* Grinding in reverse and hard shifting: This points to a problem with the transmission itself, possibly related to the clutch not fully disengaging, or internal transmission damage. The fact that it's worse in reverse suggests a problem with the reverse gear synchronizers or related components within the transmission. The new clutch kit and master cylinder replacements *should* have eliminated clutch-related causes for hard shifting, but since the problem persists, the problem lies elsewhere.
* Shakes when going into first if the car isn't moving: This is another strong indicator of a transmission problem. It could be related to the reverse gear issue, worn synchronizers in first gear, or a problem with the input shaft.
* Black brake fluid: This is a *completely separate* but serious issue. Black brake fluid means it's contaminated, likely with burnt particles from the brake system itself. This indicates potential problems with your brake calipers, wheel cylinders, master cylinder, or even internal leaks within the brake lines. This needs immediate attention, as it's a significant safety hazard.
* You've already replaced the master clutch cylinder twice: This suggests either a problem with the installation (air in the hydraulic system, improper bleeding) or a different underlying issue in the clutch hydraulic system – perhaps a failing slave cylinder. Since the problem persists after two replacements, a thorough investigation of the entire hydraulic system is warranted.
What you should do:
1. Address the brake fluid immediately: Do NOT drive the car until this is fixed. Have a mechanic bleed the brakes and inspect the entire braking system for leaks and damage. Black brake fluid means compromised braking power and increased stopping distances, significantly impacting safety.
2. Have a qualified mechanic inspect the transmission: Given the hard shifting, grinding, and shaking, especially after replacing the clutch and master cylinder, a professional needs to diagnose the problem. It's very likely there is internal damage within the transmission requiring repair or replacement. They can determine if it's a simple adjustment or a major overhaul.
3. Re-check the clutch system: Even though you've replaced components twice, a mechanic should verify correct installation, bleeding, and the condition of all related components (slave cylinder, lines, etc.). There might be an undetected leak or a different malfunctioning part.
Do not continue driving the car with black brake fluid. The transmission problems are concerning, but compromised brakes pose an immediate and significant safety risk. Get the brakes addressed first. Then, tackle the transmission issue with a professional. It's unlikely that you can diagnose and fix these problems yourself without specialized tools and knowledge.
