Parts for your 2004 Subaru Impreza-Wheel studs nuts

2004 Subaru Impreza wheel studs and nuts — what they do and how to look after them

Based on the Subaru Factory Service Manual for the 2004 Impreza (chassis/suspension and wheels & tyres sections) and the Subaru genuine parts catalogue for the GD/GG generation, this model uses pressed-in wheel studs with separate wheel nuts (M12 x 1.25 thread, five per hub, most trims run a 5×100 PCD). So wheel studs and nuts are very much relevant to the 2004 Subaru Impreza.

On a 2004 Impreza, the wheel studs and nuts clamp the wheel and brake rotor hat firmly to the hub, keeping everything centred and secure through Aussie and Kiwi road conditions. Good clamping force keeps the wheel true, helps the brakes behave consistently, and stops that annoying shimmy at highway speeds. Subaru uses a fine M12 x 1.25 thread and a 60° conical-seat nut to match most OE and many aftermarket wheels.

As part of routine servicing or tyre rotations, it pays to give the studs and nuts a quick once-over. Look for chewed or stretched threads, surface rust, or nuts with damaged seats. If a nut won’t run on by hand, don’t force it with a rattle gun — that’s how studs get cross-threaded. Clean the hub face so the wheel sits flat, fit the nuts by hand, then tighten in a star pattern with a torque wrench to the factory spec. Recheck torque after 50–100 kilometres, especially after wheel or tyre work.

They should never be lubricated — no grease or anti-seize on the threads or seats — as that changes friction and can lead to over-tightening. A light nylon-brush clean is fine if there’s light corrosion. On coastal cars, keep an eye out for heavier rust and replace affected hardware in sets.

When to replace? Any time there’s thread damage, visible necking/stretch, a snapped stud, nuts that keep working loose, or a stud that spins in the hub. Subaru’s studs are pressed into the hub from the back. Replacement typically involves:

1. Remove the wheel, then the brake caliper and rotor if access is tight.
2. Press or drive the damaged stud out while supporting the hub (avoid shocking the wheel bearing).
3. Draw the new stud fully home from the rear using a spacer stack and a sacrificial nut, or a press.
4. Refit the rotor and caliper, then the wheel, tighten nuts in a star pattern to spec and recheck after a short drive.

Stick with the correct conical-seat nuts, ensure at least 7–8 full turns of engagement on each nut, and use the impact gun for removal only. Treated right, the Impreza’s studs and nuts will quietly get on with the job, lap after lap and kilometre after kilometre.

Popular questions about 2004 Subaru Impreza wheel studs and nuts

What thread size are the wheel nuts on a 2004 Subaru Impreza?
They’re M12 x 1.25 with a 60° conical seat, five per wheel on most 2004 Impreza trims (common 5×100 PCD). That fine thread is typical Subaru fare, so match your nuts and accessories to that spec.

How tight should the wheel nuts be on a 2004 Impreza?
Use a calibrated torque wrench and the star pattern, tightening to the specification in the Subaru service data or owner’s handbook. Avoid “sending it” with an impact gun for final tightening, and recheck torque after 50–100 km.

Can a broken wheel stud be replaced at home?
Yes, if comfortable with brakes-off work and you’ve got the right tools. Support the hub, press or draw the stud in square, and avoid hammering that could stress the wheel bearing. If in doubt, a pro can do it quickly and save the hub and bearing from collateral damage.