Turbos

Ensure proper sealing when installing the turbos on your N54.

Kit includes:

• 16 - ASA M7x39 studs
• 16 - Flange nuts
• All required gaskets and o-rings
• Water pump install hardware
• Replacement vacuum hose
• T-bolt clamps

Helpful hints:

For complete installation instructions, refer to Haynes Service Manual (T#193950).

Both downpipes must be removed to remove either front or rear turbo. Tie rod end may need to be separated from knuckle for clearance. Steering rack may also need to be rotated away from subframe for access. Valve cover heat shield will need to loosened and pushed upward to get clearance for turbo manifold removal.

If studs back out of cylinder head and nuts are seized to studs, replace studs. Thread studs in to head by hand to prevent cross threading. When installing the new studs in the cylinder head, use a high temperature loctite in the cylinder head side, and copper anti-seize on the nut side.

To make more room for access to the front turbo, remove the rubber line running in front of the subframe that attaches to the back of the map thermostat and remove the clip. Cut off the OEM clamp and replace it with a new hose clamp as well.

Complete removal of the water pump is not required. Detach the water pump from the side of the block and push it out of the way to make more room for access to the front turbo. If water pump is unbolted from the block, the aluminum bolts must be replaced.

Torque specs:
Bracket to cylinder head: 9Nm
Coolant supply line to crankcase: 9Nm
Coolant return line to crankcase: 8Nm
Coolant return line to turbo: 8Nm
Coolant supply line to supply line: 8Nm
Exhaust manifold heat shield: 8Nm
Oil supply line to crankcase: 20Nm
Oil pressure line to turbo: 8Nm
Oil return line to crankcase: 8Nm
Oil return line to turbo: 8Nm
Turbo manifold to head: 20Nm

Turbo maintenance has become part of our daily lives here. Our Service department does several turbo overhauls, wastegate adjustments, carbon cleaning, and upgrades every week. For the DIY owner, however, having a complete overhaul kit takes some of the stress out of 135/535 turbo replacement and this kit includes all of the basic items. It's highly likely N54 turbos will have to be replaced before 100,000 miles. Signs of a failing turbo are high oil consumption and blue smoke from exhaust (not from a leak or failing CCV system) because the internal oil seals are no longer retaining oil. Without critical lubrication and cooling effects from oil, the turbo shafts and bearings are usually the first to wear and that requires a complete rebuild. You might also see increased turbo lag or failure to hold boost, which is usually a sign of a failing wastegate or some other internal issue. With any internal problems the turbos need to be replaced. 

This package uses new (not rebuilt) Mitsubishi turbochargers (the original supplier to BMW). These are essentially direct replacement turbos but we went straight to the manufacturer instead of going through BMW. They are the same as the factory turbos but without a BMW logo so you save yourself a few hundred dollars. It includes everything that needs replacement during a 135 or 535 N54 twin turbo overhaul -

• Front and rear new OEM Mitsubishi turbos (the original supplier of BMW turbos)
• 1 gallon of Genuine BMW coolant
• ​16 - ASA M7x39 studs
• 16 - Flange nuts
• All required gaskets and o-rings
• Water pump install hardware
• Replacement vacuum hose
• T-bolt clamps

These are brand-new turbos so a core charge does not apply.

Turbo maintenance has become part of our daily lives here. Our Service department does several turbo overhauls, wastegate adjustments, carbon cleaning, and upgrades every week. For the DIY owner, however, having a complete overhaul kit takes some of the stress out of 335 turbo replacement and this kit includes all of the basic items. It's highly likely N54 turbos will have to be replaced before 100,000 miles. Signs of a failing turbo are high oil consumption and blue smoke from exhaust (not from a leak or failing CCV system) because the internal oil seals are no longer retaining oil. Without critical lubrication and cooling effects from oil, the turbo shafts and bearings are usually the first to wear and that requires a complete rebuild. You might also see increased turbo lag or failure to hold boost, which is usually a sign of a failing wastegate or some other internal issue. With any internal problems the turbos need to be replaced. 

This package uses new (not rebuilt) Mitsubishi turbochargers (the original supplier to BMW). These are essentially direct replacement turbos but we went straight to the manufacturer instead of going through BMW. They are the same as the factory turbos but without a BMW logo so you save yourself a few hundred dollars. It includes everything that needs replacement during a 335 N54 twin turbo overhaul -

• Front and rear new OEM Mitsubishi turbos (the original supplier of BMW turbos)
• 1 gallon of Genuine BMW coolant
• ​16 - ASA M7x39 studs
• 16 - Flange nuts
• All required gaskets and o-rings
• Water pump install hardware
• Replacement vacuum hose
• T-bolt clamps

These are brand-new turbos so a core charge does not apply.