Parts for your 2020 Subaru Legacy-Universal joints

2020 Subaru Legacy universal joints: what they are and how to look after them

Based on factory documentation and parts listings, universal joints are fitted to the 2020 Subaru Legacy’s propeller shaft. Subaru’s 2020 Legacy/Outback service manual (STIS, Drive Shaft/Propeller Shaft section) specifies a two-piece propeller shaft with a centre support bearing and cardan-type universal joints that are permanently lubricated and not serviced separately. The official Subaru parts catalogue (FAST, PNC 27111 – Propeller Shaft Assembly) lists the complete shaft as an assembly, with universal joints not supplied as individual parts. Major aftermarket catalogues for the 2020 Legacy AWD also describe complete replacement shafts that include sealed U-joints. That mix of service-manual procedure and parts data confirms the vehicle does use universal joints.

On this model, the universal joints sit at the ends of the prop shaft, letting it transmit drive from the transmission to the rear differential while accommodating suspension movement and small alignment changes. They’re a quiet achiever: get them right and the car tracks smoothly, let them wear and you’ll feel shudders or hear clunks on take-off.

Because the OEM U-joints are sealed, there’s no greasing nipple and no scheduled lubrication. The practical approach in Australia and New Zealand is to have them inspected at each routine service, especially if the car does lots of coastal, gravel, or towing work. Checks typically include:

• Rotational play at each joint and the prop shaft flanges
• Signs of red/brown dust around caps, weeping seals, or heat discolouration
• Condition of the centre support bearing and its rubber mount
• Any driveline vibration between 60–100 km/h under load or a clunk when shifting from reverse to drive

If there’s wear or binding, the factory procedure is to replace the complete propeller shaft assembly rather than pressing in new joints. Many workshops will also replace the centre support bearing if it shows cracking or roughness. On refit, correct phasing and alignment matter for balance, and flange bolts should be torqued to spec with new hardware if required. Typical workshop time is around 1–2 hours on a hoist.

For owners who want a longer-term service path, some aftermarket shafts are built with circlip-style, replaceable U-joints, they can be a smart upgrade if the car sees higher kilometres or rougher roads. Either way, early attention to any vibration or clunk saves tyres, diff mounts, and the transmission from unnecessary grief.

FAQs

Do 2020 Subaru Legacy models actually have universal joints?

Yes. The 2020 Legacy’s AWD system uses a two-piece propeller shaft with cardan-type universal joints and a centre support bearing. Subaru’s service manual details removal/installation of the complete shaft and identifies the sealed U-joints as part of that assembly.

Subaru’s parts catalogue also lists the propeller shaft as a complete unit, which is why dealerships replace the whole assembly if the joints wear.

What are the tell-tale signs the Legacy’s U-joints need attention?

Common flags are a dull clunk shifting between drive and reverse, vibration or a droning feel between about 60–100 km/h under load, and rust-coloured dust near the bearing caps. You might also notice a shudder on take-off, especially up hills.

Any of those symptoms warrant an inspection of the U-joints and the centre support bearing before they escalate into more expensive driveline wear.

Can the 2020 Legacy’s U-joints be greased or replaced on their own?

From the factory they’re sealed and not serviceable on their own, so the standard fix is a complete prop shaft replacement. Some aftermarket shafts use rebuildable, clip-retained U-joints, which can be replaced individually in future.

If you’re considering that route, chat with a workshop that’s familiar with Subaru driveline balance and phasing so you keep the car smooth and quiet.