Downpipe

Remove and replace the exhaust downpipes connecting the turbochargers to the catalytic converters on the 2017 Maserati Levante 3.0L V6 Twin Turbo.

Warnings

Tools required

Parts

• Downpipe gasket set × 1 — Use OEM specification
• Exhaust flange gaskets × 2 — Use OEM specification
• O2 sensor (if damaged) × 2 — Use OEM specification

Preparation

1. Ensure engine is completely cold to the touch
2. Raise vehicle on lift or secure on jack stands at proper lifting points
3. Remove engine undertray and splash shields for access
4. Apply penetrating oil to all exhaust fasteners and O2 sensor threads
5. Disconnect negative battery terminal to prevent O2 sensor codes during removal

Procedure

1. 1

   Remove heat shields
   Remove the turbocharger and downpipe heat shields by removing the mounting bolts. There are multiple shields covering the turbochargers and upper downpipe sections. Keep track of shield positions for reassembly.
   Torque spec

   Heat Shield Bolts10 Nm (7 lb-ft)
2. 2

   Disconnect oxygen sensors
   Disconnect the electrical connectors for all four oxygen sensors (two pre-cat and two post-cat). Press the connector release tabs and carefully pull connectors apart. Using an O2 sensor socket or 22mm wrench, remove the oxygen sensors from the downpipes. Turn counterclockwise and remove carefully to avoid damage.
   ⚠O2 sensor wires are fragile. Support the sensor body while loosening to prevent wire damage.
   Torque spec

   O2 Sensor45 Nm (33 lb-ft)
3. 3

   Remove driver side downpipe upper connection
   Working from above the engine bay, locate the driver side downpipe connection to the turbocharger outlet. Remove the three flange nuts connecting the downpipe to the turbo. The connection is difficult to access and may require universal joint sockets or swivel extensions.
   Torque spec

   Manifold Nuts35 Nm (26 lb-ft)
4. 4

   Remove passenger side downpipe upper connection
   Locate the passenger side downpipe connection to the turbocharger outlet. Remove the three flange nuts connecting the downpipe to the turbo. Access is similarly restricted on this side.
   Torque spec

   Manifold Nuts35 Nm (26 lb-ft)
5. 5

   Disconnect downpipe hangers
   From underneath the vehicle, locate the rubber exhaust hangers supporting the downpipes. Remove the hanger mounting bolts or use a pry bar to carefully release the hangers from their mounts. Note hanger positions for reassembly.
   Torque spec

   Hanger Bolts22 Nm (16 lb-ft)
6. 6

   Remove lower flange connections
   Locate the flange connections where the downpipes connect to the catalytic converters or mid-pipes. Remove the flange bolts on both driver and passenger sides. There are typically 2-3 bolts per flange connection. Support the downpipes while removing final bolts.
   ⚠Downpipes are heavy and awkward to maneuver. Have an assistant support the pipes or use a transmission jack.
   Torque spec

   Exhaust Flange Bolts45 Nm (33 lb-ft)
7. 7

   Remove downpipes
   Carefully lower and maneuver the downpipes from the vehicle. They must be angled and rotated to clear the transmission crossmember, driveshaft, and frame components. Work slowly and check clearances to avoid damaging brake lines or wiring.
8. 8

   Clean mating surfaces
   Use a wire brush to thoroughly clean all flange mating surfaces on the turbocharger outlets, catalytic converter inlets, and exhaust system. Remove all old gasket material, carbon deposits, and corrosion. Inspect flanges for warping or damage.
9. 9

   Install new downpipes
   Install new gaskets on all flange connections. Apply anti-seize compound to turbocharger flange studs and lower flange bolt threads. Carefully maneuver new downpipes into position, aligning upper turbo flanges first. Thread nuts onto turbo flanges hand-tight but do not fully tighten yet.
10. 10

    Connect lower flanges
    Align the lower flange connections to the catalytic converters or mid-pipes. Install new flange gaskets and insert bolts. Hand-tighten all bolts to ensure proper alignment before final torque.
11. 11

    Torque all flange connections
    Starting with the upper turbocharger connections, torque the manifold nuts in a cross pattern to specification. Then torque the lower flange bolts in a cross pattern. Ensure anti-seize was applied to all threaded fasteners.
    Torque spec

    Manifold Nuts35 Nm (26 lb-ft)

    Exhaust Flange Bolts45 Nm (33 lb-ft)
12. 12

    Reinstall exhaust hangers
    Reconnect the rubber exhaust hangers to their mounts. Install and torque hanger bolts to specification. Ensure downpipes hang properly without strain on any connection points.
    Torque spec

    Hanger Bolts22 Nm (16 lb-ft)
13. 13

    Install oxygen sensors
    Apply a small amount of anti-seize compound to the threads of each oxygen sensor (avoid getting compound on the sensor tip). Thread sensors into the downpipes by hand, then torque to specification using an O2 sensor socket. Reconnect all four O2 sensor electrical connectors.
    ⚠Only apply anti-seize to threads, never to the sensor element. Contamination will cause sensor failure.
    Torque spec

    O2 Sensor45 Nm (33 lb-ft)
14. 14

    Reinstall heat shields
    Reinstall all turbocharger and downpipe heat shields in their original positions. Install and torque heat shield bolts to specification. Ensure shields do not contact any moving parts or wiring.
    Torque spec

    Heat Shield Bolts10 Nm (7 lb-ft)

Reassembly

1. Reconnect negative battery terminal
2. Reinstall engine undertray and splash shields
3. Lower vehicle from lift or jack stands
4. Start engine and listen for exhaust leaks at all flange connections
5. Clear any diagnostic trouble codes related to O2 sensor disconnection using scan tool

Verification

• Start engine and verify no exhaust leaks at turbo flanges or lower connections
• Check that all heat shields are secure and not rattling
• Take vehicle for test drive and verify no exhaust drone or abnormal sounds
• Confirm all O2 sensors are reading properly with no check engine light
• Perform visual inspection from underneath to verify no exhaust components contacting chassis or driveline
• Re-torque all flange connections after 50-100 miles of driving

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