N54 belt & tensioner

[relative4]

After reading umpteen posts about serpentine belts that grenaded through the front seal, I have decided to proactively replace the belt and tensioner on my '07 335xi E90 auto. Anyone have input on the best manufacturer for each? Don't care about price. Just stick with OEM? Thanks!

[RocketSurgeon]

OEM for sure.
The ones I've bought locally have made noise within 6 months. I'm not playing games with an N54, only OEM.

[relative4]

According to what I'm seeing from various sources, the OEM belt is a Contitech and the OEM tensioner is made by INA. Can anyone confirm whether this is correct?

[White94RX]

Good luck. Changing the belt is notoriously difficult on the N54 thanks to the intake pipe that runs directly in front of the tensioner spot for the T60.

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[relative4]

Good luck. Changing the belt is notoriously difficult on the N54 thanks to the intake pipe that runs directly in front of the tensioner spot for the T60.

Good thing I stayed at a Holiday Inn Express last night.

Re the tensioner, I'm seeing mixed reviews on whether the Schwaben tool is any better than a socket. Can anyone comment on that?

[White94RX]

If there's a special tool, I need to buy one. Using a socket and an open end wrench that fits the bit part of the socket sucks.

I always undo the two t30 screws that hold the intake pipe to the head for extra room

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[E36M30924]

I just did this. I used a t60 bit to release tension. I git my belt from Auto Zone (dayco) and I got my belt tensioner from ECS. job took 45 min. like someone else said take the two bolts that hold the intake pipe on and the fan out and you will have loads of room.

[relative4]

Just got done replacing the belt, tensioner, and both idlers. Some observations:

• I bought a Contitech belt, which is definitely OEM, and French INA tensioner and pulleys, which are also billed as OEM. I got the whole set for $130 on eBay. The original pulleys turned out to be Boesner, but I can't find that supplier anywhere online. The tensioner did not come with a dustcap for the fixed pulley, not sure if that's normal or if it was missing, but the old dustcap fit perfectly, so no harm done.
• When unbolting the front turbo inlet from the block, the bolts are retained in the inlet flange. If you manage to back one of them out too far (hypothetically speaking), reinstall it while the tensioner is out. More space to work with.
• Replacing the idlers requires removing the radiator fan. The hardest part of that is detaching the intercooler-TB pipe from the rubber mount on the fan shroud. If you have an automatic transmission, note you'll need to remove the belly pan (14 screws) to remove the ATF cooler from the fan shroud.
• You may want to remove the radiator fan regardless, makes everything easier.
• You may want to remove the belly pan regardless, makes routing the new belt easier.
• Pulleys torque to 38Nm; tensioner torques to 40Nm.

Everything was still in great shape, but now I can breathe easy without that ticking time bomb.