Parts for your 2017 Subaru Legacy-Driveshafts

2017 Subaru Legacy driveshafts — what they do and when to service them

Driveshafts absolutely are relevant to the 2017 Subaru Legacy (BN). Technical references such as the Subaru Service Manual (Driveline/Axle and Propeller Shaft sections), the Subaru Technical Information System workshop literature for BN/BS models, and the Genuine Subaru Parts Catalogue for the BN Legacy all document a centre propeller shaft linking the transmission to the rear differential, as well as front and rear drive axles (CV half-shafts). As an all-wheel drive sedan, the 2017 Legacy relies on these shafts to deliver torque to both axles.

In plain terms, the driveshafts form the backbone of Subaru’s Symmetrical AWD. The centre propeller shaft carries engine torque rearward, while the four CV half-shafts at the wheels transfer power through constant-velocity joints that allow suspension movement and steering. When everything’s healthy, the car feels planted and smooth, when not, vibrations, clunks, or clicks can creep in.

For servicing, regular inspection goes a long way. At routine services (every 10–15,000 km is a good habit), a technician should:

• Check CV boots for splits and grease sling, especially after gravel-road use.
• Listen for clicking on full lock (outer CVs) and feel for shudder under load (inner joints or prop shaft issues).
• Inspect the prop shaft centre support bearing and look for play, many BN shafts have non-serviceable U-joints, so the assembly is replaced if worn.

If replacement is needed, quality matters. Genuine or reputable aftermarket shafts keep balance and NVH in check. It’s smart practice to replace axle nuts and hub seals, torque fasteners to factory spec, and mark prop shaft flanges before removal to preserve balance. After fitment, a road test to verify vibration-free running is essential.

Warning signs owners report include:

• Grease mist inside the wheel arch or underbody.
• Clicking on low-speed turns.
• Vibration between 60–100 km/h or a driveline thrum at steady cruise.
• A dull clunk selecting Drive/Reverse that isn’t due to mounts or diff bushes.

Driven gently on sealed roads, driveshafts can run well past 150,000 km. Frequent corrugations, towing, or lowered/raised suspension can accelerate wear, so more frequent checks make sense for Aussie and Kiwi conditions.

Popular questions about 2017 Subaru Legacy driveshafts

Does a 2017 Subaru Legacy have a driveshaft?
Yes. The BN Legacy uses a centre propeller shaft for the AWD system plus front and rear CV half-shafts. This layout is confirmed in Subaru’s BN/BS workshop manuals and parts catalogues for the 2015–2019 generation.

How long do the driveshafts last on a 2017 Legacy?
Many see 150,000–250,000 km or more, but CV boots can perish earlier. Gravel roads, heavy loads, or modified ride heights can shorten life. Regular inspections and prompt boot repairs help avoid full shaft replacement.

Is it safe to drive with a vibrating driveshaft?
It’s not recommended. Ongoing vibration can stress bearings, the centre support, and even the transmission or differential. It’s best to have the issue diagnosed and fixed before it snowballs.