Parts for your 2015 Mitsubishi Asx-Drive belt tensioner

2015 Mitsubishi ASX drive-belt-tensioner: what it does and when to service it

Yes, the 2015 Mitsubishi ASX uses a drive-belt tensioner. Technical references that confirm this include the Mitsubishi ASX/RVR/Outlander Sport Workshop Manual (Drive Belt – Removal/Installation section), which specifies an automatic accessory drive-belt tensioner with no belt adjustment required, and the Mitsubishi ASA electronic parts catalogue, which lists a “TENSIONER, DRIVE BELT” for 2015 ASX variants (including 2.0L 4B11 petrol and 1.8 Di‑D). Aftermarket technical catalogues from Gates and Dayco for the 2015 ASX also catalogue a direct-fit automatic belt tensioner assembly for these engines.

On a 2015 Mitsubishi ASX, the drive-belt tensioner keeps the serpentine belt at the sweet spot for tension so the alternator, air-con compressor and (where fitted) power steering pump all run smoothly. It’s a spring-loaded unit that constantly takes up slack as the belt beds in and as loads change, so there’s no mucking about with manual adjustments. That means fewer squeals on cold starts, better charging, and steadier A/C performance.

While the tensioner isn’t a scheduled replacement item by time alone, it’s smart to have it inspected at each service. A good rule of thumb is to give it extra attention from about 100,000 km and expect replacement somewhere around 120,000–160,000 km, or earlier if it’s noisy or the belt tracks poorly. Signs it’s on the way out include a chirp or squeal that returns quickly after fitting a new belt, belt flutter at idle, visible misalignment, a wandering belt, or a tensioner arm that sits outside its wear indicator range. You might also notice a battery light flicker, heavy steering (if hydraulic), or weak A/C output.

Replacement is straightforward for a competent DIYer, but most owners will prefer a workshop to avoid hassles. The technician will:

• Remove the right-hand splash guard for access (common on ASX).
• Use the hex boss on the tensioner to relieve tension and slip off the belt.
• Check all pulleys and the overrunning alternator pulley, then fit the new tensioner and a fresh belt if needed.

Always follow the factory belt routing diagram and use quality parts. If there’s any doubt about torque specs or routing, the workshop manual is the go-to. Pairing a new belt with a new tensioner is a solid move to avoid comebacks, especially in hot Aussie and Kiwi conditions.

• Does the 2015 Mitsubishi ASX have a drive-belt tensioner?
  Yes. It uses a spring-loaded automatic tensioner on the accessory (serpentine) belt. There’s no manual belt adjustment on this model.
• How often should the drive-belt tensioner be replaced on a 2015 ASX?
  Inspect it at every service. Many last 120,000–160,000 km, but replace sooner if there’s noise, misalignment, poor belt tracking or the indicator is out of range.
• What are the symptoms of a failing drive-belt tensioner on a 2015 ASX?
  Cold-start squeals that return quickly after a new belt, belt flutter, visible pulley wobble or misalignment, battery light flicker, heavier steering (if hydraulic), or intermittent A/C drive.