Brake Hose - Rear

Replace a rear brake hose on a 2024 Model S Long Range AWD. This is a hydraulic-only job that does not touch HV systems, but requires brake bleeding afterward and proper handling of the aluminum chassis hardware.

Warnings

Tools required

Parts

• Rear brake hose assembly (manufacturer-specified for 2024 Model S LR AWD) × 1 — OEM Tesla rear brake hose — verify by VIN
• Copper sealing washers for banjo fitting × 2 — OEM-spec copper crush washers, sized to banjo bolt

Fluids

• DOT 3 Brake Fluid (verify spec by VIN — some newer Model S use DOT 4) — 1 qt

Preparation

1. Park on level ground, place in P, engage the parking brake.
2. Exit ALL doors with the 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 in the front trunk (frunk) under the nose cowl panel. (If this vehicle is equipped with a 16V Li-ion unit, follow the appropriate disconnect procedure for that unit.)
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 Service Mode is NOT required for this hydraulic job, but confirm the vehicle will not auto-wake by keeping the key fob outside the work area.
7. Loosen the rear lug nuts on the affected side while the wheel is still on the ground.
8. Lift the vehicle at the manufacturer-specified rear jack point using puck adapters and support on jack stands.
9. Remove the rear wheel and set aside on its face to protect the finish.
10. Place a catch pan beneath the rear caliper area to capture brake fluid.
11. Have replacement copper washers and the new brake hose ready before opening the hydraulic system.

Procedure

1. 1

   Inspect and identify hose routing
   Trace the rear brake hose from the hard line union at the body/subframe down to the caliper banjo fitting. Note the routing through any intermediate brackets and the orientation of the hose clip(s). Take a photo for reassembly reference. Verify there are no orange HV cables in the immediate work zone.
2. 2

   Cap the master cylinder reservoir
   Open the frunk and locate the brake fluid reservoir. Remove the cap, then place a plastic film or brake-fluid-safe stopper over the opening to slow fluid loss via siphoning while the line is open. Do not let the reservoir run dry during the job.
   ⚠Brake fluid is hygroscopic — keep the reservoir capped or covered as much as possible.
3. 3

   Loosen the hard-line fitting at the hose
   Using a flare-nut wrench, slightly loosen (do not remove) the hard brake line nut threaded into the upper end of the rubber hose. Use a back-up wrench on the hose hex to prevent twisting the hose. Re-snug it temporarily to minimize drip until you are ready to disconnect.
   ⚠Always use a flare-nut wrench on hydraulic fittings. An open-end wrench will round the nut.
4. 4

   Remove the banjo bolt at the caliper
   Position the catch pan under the caliper. Remove the banjo bolt securing the lower end of the hose to the rear caliper. Discard the two copper washers — they must not be reused. Allow residual fluid to drain into the pan.
   Torque spec

   Brake Hose Banjo Bolt25 Nm (18 lb-ft)
5. 5

   Release the hose retaining clip(s) and bracket(s)
   Remove any spring clip retaining the hose to the chassis bracket at the body-side end. If the hose is secured by a small bolted bracket along its run, remove that fastener as well. Note the orientation of any anti-rotation tabs.
   Torque spec

   Brake Hose Bracket10 Nm (7 lb-ft)
6. 6

   Disconnect the hard line and remove the old hose
   Fully unthread the hard line nut from the upper hose fitting using a flare-nut wrench with a back-up wrench. Cap the open hard line immediately to prevent contamination. Withdraw the old hose assembly from the vehicle.
   ⚠Do not allow the open hard line to touch dirt or shop debris — contamination will damage ABS/iBooster internals.
7. 7

   Install the new hose — body end first
   Position the new hose in its bracket(s) with anti-rotation tabs seated. Hand-thread the hard line nut into the new hose fitting to avoid cross-threading, then snug with the flare-nut wrench while holding the hose hex with a back-up wrench. Final torque per Tesla service manual specification for the hard-line union (use a line wrench torque adapter if available).
   ℹ️Torque the hard-line tube nut to OEM specification — refer to Tesla Service Manual. Do not over-torque or the flare seat will deform.
   Torque spec

   Brake Hose Bracket10 Nm (7 lb-ft)
8. 8

   Install the banjo bolt at the caliper
   Place a NEW copper washer on each side of the banjo eyelet (one between bolt head and hose, one between hose and caliper). Thread the banjo bolt by hand, then torque to spec. Verify the hose is not twisted and has full clearance through suspension travel.
   ⚠New copper washers are mandatory. Reusing crushed washers will cause a slow leak and brake failure.
   Torque spec

   Brake Hose Banjo Bolt25 Nm (18 lb-ft)
9. 9

   Verify hose routing through suspension travel
   With the wheel still off, cycle the suspension by hand if possible and check that the new hose does not contact the tire, control arms, or any rotating components at full droop or full compression. Confirm there is no twist in the hose between the upper and lower fittings.
10. 10

    Bleed the rear brake circuit
    Top off the master cylinder reservoir with the correct DOT specification fluid (verify DOT 3 vs DOT 4 by VIN). Bleed the affected rear caliper at its bleeder screw using a vacuum or pressure bleeder until clean, bubble-free fluid flows. Keep the reservoir topped off throughout. Tesla typically recommends bleeding via Service Mode-initiated ABS self-bleed for a complete job — if Service Mode/Toolbox is not available, perform a thorough manual bleed and have the vehicle scanned afterward.
    ⚠Do not mix DOT 3 and DOT 5 fluids. Verify the correct DOT specification for this VIN before adding fluid.
    Torque spec

    Bleeder Screw14 Nm (10 lb-ft)
11. 11

    Leak check under pressure
    With the 12V reconnected after bleeding (or with an assistant pumping a manual brake pedal if 12V is still disconnected), apply and hold firm pedal pressure. Inspect the banjo fitting and hard-line union for any seepage. Wipe dry and re-check after several pedal applications.

Reassembly

1. Confirm the bleeder screw is closed and torqued to spec, with its dust cap installed.
2. Top off the brake fluid reservoir to the MAX line and reinstall the cap.
3. Reinstall the rear wheel. Snug lug nuts in a star pattern by hand.
4. Lower the vehicle to the ground.
5. Final-torque the lug nuts in a star pattern.
6. Reconnect the 12V (or 16V) low-voltage battery.
7. Close the frunk and allow the vehicle to fully wake; verify no brake-related alerts on the touchscreen.

Verification

• With the vehicle awake, confirm no ABS, traction control, or brake system warnings appear on the center display.
• Pump the brake pedal — it should feel firm within 1–2 strokes with no sponginess. A soft pedal indicates trapped air; re-bleed.
• Visually re-inspect the banjo fitting and hard-line union for leakage after the first drive.
• Perform a low-speed brake test in a safe area (5–10 mph) before road use; confirm the vehicle pulls straight with normal pedal effort.
• After a short test drive, re-check the fluid level and re-inspect both fittings for weeping.
• Note: Tesla recommends full brake fluid replacement every 2 years regardless of mileage. If the existing fluid was older than that or appeared dark, perform a complete 4-corner flush at this time.
• If Tesla Toolbox or Service Mode is available to a certified tech, request an ABS pump self-bleed cycle to evacuate any air trapped in the modulator.

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

Chasing one of these codes and not sure which part is guilty? Ask a master mechanic about YOUR car →

More procedures for this vehicle