Complete replacement of all hydraulic brake lines on a 2024 Model Y Long Range AWD, including hard lines and flexible hoses at all four corners, followed by a full system bleed. This is a wet job requiring careful protection of the aluminum body and painted surfaces from DOT 3 brake fluid.

Warnings

Tools required

Parts

• Front flexible brake hose (LH) × 1 — OEM Model Y front brake hose, left
• Front flexible brake hose (RH) × 1 — OEM Model Y front brake hose, right
• Rear flexible brake hose (LH) × 1 — OEM Model Y rear brake hose, left
• Rear flexible brake hose (RH) × 1 — OEM Model Y rear brake hose, right
• Hard line set (front-to-rear and master cylinder runs) × 1 — OEM-equivalent pre-formed steel/nickel-copper lines to Tesla spec
• Copper/aluminum sealing washers for banjo fittings (if equipped) × 8 — Manufacturer-specified crush washers
• Hose retaining clips × 4 — OEM bracket clips

Fluids

• DOT 3 Brake Fluid (fresh, sealed) — 1.5 qt

Preparation

1. Park on level ground, place in P, engage parking brake.
2. Exit ALL doors with key fob away from the vehicle. Wait at least 2 minutes for HV systems to fully de-energize, even on this non-HV job.
3. Disconnect the 12V low-voltage battery (located under the rear seat / rear cargo area trim on 2024 Model Y — refer to Tesla's first-responder/service location for this build). Use an insulated wrench and isolate the negative terminal.
4. DO NOT touch, cut, or pierce ANY orange cable — these are high-voltage and lethal.
5. If at any point you encounter an orange cable, an HV component, or are unsure if a system is de-energized: STOP and consult a Tesla-certified technician.
6. Place the vehicle in Transport/Tow Mode workflow before 12V disconnect if you need to release the electronic parking brake for wheel work; otherwise leave EPB engaged.
7. Loosen all five wheel lug nuts on each wheel before lifting.
8. Raise the vehicle on a lift or jack stands using only Tesla-approved jack points with rubber pucks.
9. Remove all four wheels.
10. Stage absorbent pads under each caliper, along the line routing, and under the master cylinder area.
11. Have the new brake lines laid out and matched to the OEM lines BEFORE removal so routing and clip locations are confirmed.

Procedure

1. 1

   Cap reservoir and pre-empty the system
   Open the hood and access the brake fluid reservoir on the brake actuator/booster assembly. Use a fluid extractor to remove as much old DOT 3 fluid as possible from the reservoir to minimize spillage during line removal. Do NOT press the brake pedal. Leave the reservoir cap loosely set on top to limit airborne moisture ingress.
   ⚠Do not allow the reservoir to empty completely into the actuator — keep a small residual to prevent ingesting air into the iBooster pump.
2. 2

   Document line routing
   Photograph the entire hard-line routing along the underbody, the rear axle area, and front strut towers. Note every retaining clip, p-clamp, and grommet position. Tesla routes the rear lines along the battery pack perimeter — keep clear of pack seams and HV harness conduits.
3. 3

   Disconnect flexible hoses at each caliper
   At each corner, place a catch pan beneath the caliper. Using a flare/line wrench, loosen the hose-to-caliper fitting (banjo bolt or threaded union as equipped). Cap the caliper port immediately. If the caliper itself is being left in place, support the caliper with a hanger — do NOT let it dangle from any line or wiring.
   ⚠Do not twist the flex hose while breaking the fitting — counter-hold with a second wrench on the hex of the hose end.
   Torque spec

   Line Fittings20 Nm (15 lb-ft)
4. 4

   Disconnect flexible hoses at chassis/hardline junctions
   At each corner the flex hose terminates at a chassis bracket where it joins a hard line via a union nut and retaining U-clip. Remove the U-clip first, then back off the hard-line fitting with a line wrench while holding the hose hex. Cap both ends. Repeat for all four corners.
   ℹ️If the U-clip is corroded or distorted, replace it — these are inexpensive and critical to retaining the hose body.
   Torque spec

   Line Fittings20 Nm (15 lb-ft)
5. 5

   Remove hard line clips and brackets
   Working from rear to front, release every p-clip, push-pin retainer, and bracket bolt securing the hard lines to the underbody and subframes. Where bracket bolts thread into chassis nutserts, note their location for reinstallation.
   ⚠Tesla underbody panels are aluminum/composite. Do not pry against the battery pack enclosure or its sealing flange.
   Torque spec

   Bracket Bolts102 Nm (75 lb-ft)

   Mounting Bolts27 Nm (20 lb-ft)
6. 6

   Disconnect hard lines at the brake actuator
   In the front trunk area, identify the hard-line outputs from the brake actuator/master assembly. Place absorbent material beneath. Use a line wrench to loosen each output fitting one at a time, capping the actuator port immediately to prevent fluid loss and contamination. Note the position of each line (primary/secondary circuits).
   ⚠️Do not apply force to the actuator body — internal solenoids and pressure sensors are easily damaged. If a fitting is seized, stop and consult the service manual.
   ⚠Brake fluid dripping onto the front trunk liner or paint will cause permanent damage. Flood with water if spilled.
   Torque spec

   Line Fittings20 Nm (15 lb-ft)
7. 7

   Remove old hard lines from the vehicle
   Carefully extract the hard lines as a set, working them out of grommets and along their routing path. Avoid kinking adjacent lines that may be reused. Lay the removed set on the floor in the same orientation as the vehicle to use as a routing reference for the new lines.
8. 8

   Install new hard lines
   Route the new hard lines along the original path, seating them into all grommets and clips. Hand-thread every fitting first — never start a flare nut with a wrench. Once all fittings at both ends are hand-tight and lines are clipped in place, torque each fitting using a line/crowfoot adapter.
   ⚠Verify lines do not contact the battery pack enclosure, HV conduits, suspension links, or exhaust-equivalent heat shields. Maintain factory standoff distances.
   Torque spec

   Line Fittings20 Nm (15 lb-ft)

   Bracket Bolts102 Nm (75 lb-ft)

   Mounting Bolts27 Nm (20 lb-ft)
9. 9

   Install new flexible hoses
   Install each flex hose at the chassis bracket first: thread the hard-line union by hand, install the U-retaining clip, then torque the union. Next attach the caliper end with new sealing washers (if banjo style) or by threading the union directly. Ensure the hose is not twisted — observe the molded orientation marks and bracket tabs.
   ⚠Cycle the suspension and steering through full travel before torquing the hose ends to confirm no contact, stretch, or twist.
   Torque spec

   Line Fittings20 Nm (15 lb-ft)
10. 10

    Refill reservoir with fresh DOT 3
    Fill the reservoir to MAX with fresh, sealed DOT 3 brake fluid. Keep it topped off throughout bleeding — do not let it drop below MIN or air will enter the actuator.
11. 11

    Bleed the system at each caliper
    Using a pressure or vacuum bleeder, bleed each caliper in the manufacturer-specified sequence (typically furthest from the master cylinder first). Open each bleeder screw, flow clean fluid until no air bubbles are visible, then close. Torque each bleeder screw to spec. NOTE: full Tesla iBooster/iBoost-equivalent service bleeding may require Tesla Toolbox to actuate the internal pump for a complete bleed — pedal-bleeding alone is NOT sufficient on this vehicle. If you do not have access to Toolbox, the vehicle must be taken to a Tesla-authorized facility for the actuator bleed cycle before road use.
    ⚠️Driving the vehicle without a complete actuator-side bleed may result in degraded ABS/regen blending and extended stopping distances. Do not skip the Toolbox bleed step.
    Torque spec

    Bleeder Screw10 Nm (7 lb-ft)
12. 12

    Final fitting inspection
    Wipe every fitting dry. Pressurize the system (with the bleeder) and visually inspect every union, banjo, and bracket for weeping. Re-torque any fitting that shows seepage — never overtighten beyond spec to stop a leak; replace the washer or fitting instead.
    Torque spec

    Line Fittings20 Nm (15 lb-ft)

Reassembly

1. Confirm all hard line clips and bracket bolts are torqued and lines are not contacting moving or hot components.
2. Top off the brake fluid reservoir to MAX with fresh DOT 3 and install the cap fully.
3. Reinstall any underbody aero/splash panels removed for access; torque fasteners to OEM specification — refer to Tesla Service Manual.
4. Reinstall all four wheels. Hand-thread lug nuts, then torque in a star pattern.
5. Lower the vehicle to the ground.
6. Reconnect the 12V low-voltage battery negative terminal.
7. Close hood/frunk and rear access panels.

Verification

• With the 12V reconnected and vehicle powered on (foot off brake), watch the instrument display for any ABS, Brake System, Traction Control, or Stability Control alerts. Any of these indicate the actuator still has air or a sensor issue — do not drive.
• Connect Tesla Toolbox (or have a Tesla-authorized facility do so) and run the brake actuator bleed routine. This step is mandatory after opening the hydraulic circuit on Model Y.
• With the vehicle still stationary and powered, press the brake pedal firmly several times. Pedal must be firm and consistent — a soft or sinking pedal indicates remaining air.
• Re-inspect every fitting, hose end, and bleeder screw for leaks after the Toolbox bleed cycle (system pressure is much higher than gravity bleed).
• Perform a low-speed road test in a safe area: verify smooth braking, no pulling, and that regen-to-friction blending feels normal. Recheck for leaks after the test.
• Log this service date — Tesla recommends brake fluid replacement every 2 years regardless of mileage; this complete line replacement resets that interval.
• While the wheels were off, this is also a good opportunity to verify tire rotation status — Tesla recommends rotation every 6,250 miles on Model Y due to high tire wear.

More procedures for this vehicle