* Brake System Issues:
* Proportioning Valve: This valve regulates brake pressure between the front and rear brakes. A malfunctioning proportioning valve can send too much pressure to the front brakes, causing a nosedive. This is a prime suspect given the symptoms.
* Master Cylinder: A failing master cylinder might not be providing equal pressure to all four wheels, leading to disproportionate braking and the nosedive.
* Brake Lines/Hoses: Leaks or restrictions in brake lines can also affect brake pressure distribution. Check for leaks, kinks, or rust.
* Calipers/Wheel Cylinders: Seized or sticking calipers (front brakes) or wheel cylinders (rear brakes) can cause uneven braking and contribute to the nosedive.
* Brake Booster: A vacuum leak or failing booster reduces braking assistance, which can indirectly contribute to a more aggressive nosedive as you have to apply more force to the pedal.
* Suspension System Issues (beyond shocks):
* Springs/Coil Springs: Worn or broken springs, particularly in the front, will reduce the suspension's ability to resist compression under braking, worsening the nosedive.
* Bushings: Worn or damaged control arm bushings, ball joints, or other suspension components can lead to excessive movement and a less stable braking experience. This can be exacerbated by braking.
* Steering Components: Worn tie rod ends or other steering components can lead to instability, indirectly impacting how the vehicle reacts to braking.
Troubleshooting Steps:
1. Brake System Inspection: This is the most important step. A thorough inspection by a mechanic is crucial. They should check for leaks, inspect the calipers and wheel cylinders, test the master cylinder, and examine the proportioning valve. A pressure test of the brake system is vital to pinpoint leaks or pressure imbalances.
2. Suspension Inspection: Visually inspect all suspension components for damage or wear. Look for cracks in springs, worn bushings, or damaged ball joints.
3. Road Test (with caution): Have someone experienced test drive the vehicle while carefully observing the brake pedal feel and the vehicle's reaction to braking.
4. Professional Diagnosis: Given that new shocks didn't solve the issue, taking it to a qualified mechanic is strongly recommended. They have the tools and expertise to diagnose the problem accurately.
Ignoring the issue is dangerous. Uneven braking significantly reduces stopping power and increases the risk of an accident. Get it checked out immediately.
