Buy Acura MDX Accessory Drive Belt Tensioner Assemblys

An Acura MDX accessory drive belt tensioner assembly (also called a serpentine belt tensioner, drive belt tensioner, or belt pulley assembly) is a spring-loaded part that keeps the serpentine/drive belt tight as it turns the engine's accessories. The tensioner helps the belt grip, stay aligned, and run quietly. If the tensioner wears out, the belt can slip, squeal, or jump off. Gates (a major belt system maker) explains that a weak or bouncing tensioner can overheat the belt and cause early failure. (gates.com, navigates-ws.gates.com)

On the MDX, the accessory (serpentine) belt powers key add-ons like the alternator and A/C compressor. On earlier MDX models, it also powered a hydraulic power-steering pump. Newer MDX generations use electric power steering (EPS), so there's no belt-driven steering pump on those years. Acura's 2006 Owner's Manual shows power-steering fluid service (hydraulic system), while Acura's 2014 Advanced Technology Guide lists ÒElectric Power Steering.Ó (acura.com, techinfo.honda.com)

On the MDX, the water pump is tied to the timing belt service, not the serpentine/drive belt. Acura maintenance schedules pair Òreplace timing belt and inspect water pump,Ó which means a failed serpentine belt won't usually stop coolant flow in an MDX. See the 2006 Owner's Manual and the MDX Maintenance Minder guide for examples. (acura.com, owners.acura.com)

Acura's Maintenance Minder system uses sub-codes to tell you when to inspect the drive belt (look for sub-code Ò2Ó). You can view a sample guide here: . Gates also recommends inspecting the tensioner and accessory system around 60,000 miles and replacing worn parts by about 90,000 miles. (, gates.com)

Watch and listen for:

• Chirp/squeal on start-up or when A/C turns on.
• Belt edge wear or glazing.
• Tensioner arm that jitters or Òbounces.Ó
• Intermittent battery/charging light if the alternator slips (belt-drive issue).
  Gates' technical bulletins describe how worn pivot bushings or weak dampers make the arm bounce and the belt overheat or slip. (navigates-ws.gates.com)

Normal age, heat, and vibration slowly weaken the tensioner spring and damper. Misaligned pulleys, seized idlers, or a stretched/glazed belt speed up wear. Gates notes that many Òbelt problemsÓ start at the tensioner, not the belt itself-so be sure to check the whole system. (gates.com)

Best practice is to service the system as a set: tensioner assembly, serpentine/drive belt, and any noisy idler pulleys. Complete Òbelt + tensioner + idlerÓ kits exist because these parts wear together and replacing them together cuts repeat labor. See Gates' overview of complete serpentine kits. (gates.com)

Basic steps (general guidance-always follow your model-year service info):

1. Note the under-hood belt routing label.
2. Use the square drive/hex on the tensioner to unload the belt.
3. Slip off the belt and unbolt the tensioner assembly.
4. Install the new tensioner; hand-start bolts straight; torque per your manual.
5. Route the new belt; tensioner will self-set.
6. Start engine; watch for smooth belt tracking.
   For official manuals, pick your year on the Acura Owners site.

Working near A/C lines? U.S. law requires certified handling of refrigerant. The EPA explains that Section 609 certification is required to service MVAC systems for pay, and venting refrigerant is prohibited. See: EPA MVAC Servicing Requirements and the 609 fact sheet (PDF). (US EPA)

• 2001-2006: Hydraulic power steering; drive belts are listed in the maintenance section; timing belt drives the water pump. See the 2006 Owner's Manual. (acura.com)
• 2014-present: Electric power steering (EPS), so no belt-driven PS pump. See the 2014 Advanced Technology Guide. (techinfo.honda.com)
• All years: Follow your specific owner's manual/maintenance guide for belt inspection and timing-belt/water-pump intervals. You can search by year at the Acura Owners Manuals page.

Older, pre-Maintenance-Minder schedules call for routine Òinspect drive beltsÓ at set mileages; modern MDX models use Maintenance Minder sub-codes (e.g., Ò2Ó includes Òinspect drive beltÓ). Use your VIN/year for exact timing, but always inspect sooner if you hear noise or see belt wear. Sample guides: 2018 MDX Maintenance Minder.

• Choose a tensioner assembly built for your MDX year/engine.
• Replace the belt with the tensioner to avoid come-backs.
• Check pulley alignment and spin all idlers by hand; any roughness means replace.
  These points mirror system-level advice from belt system technical bulletins. (navigates-ws.gates.com)

• Serpentine belt / drive belt: A long, ribbed rubber belt that drives engine accessories.
• Tensioner assembly: Spring-loaded arm and pulley that keeps belt tight.
• Idler pulley: A free-spinning pulley that helps route or support the belt.
• EPS: Electric Power Steering (no hydraulic pump or fluid). (techinfo.honda.com)

• Acura Owners - Manuals & Warranties (pick your year for exact steps and maintenance items).
• Acura Maintenance Minder - MDX (PDF) (how Acura signals Òinspect drive beltÓ).
• Gates Tech Tip: Diagnosing Tensioner Failure (PDF) (what to look for).
• Gates Protect The Rideª (how the serpentine system works).
• EPA MVAC Servicing Requirements (A/C refrigerant rules).
• 2014 MDX - Advanced Technology Guide (PDF) (confirms EPS).
• 2006 MDX - Owner's Manual (PDF) (older-gen hydraulic PS and maintenance tables).

The accessory drive belt tensioner on an Acura MDX is a small, spring-loaded hero. It keeps the serpentine belt tight so the alternator and A/C keep doing their jobs-and, on older MDX models, so the power-steering pump works. Inspect the belt system on schedule, and when in doubt, replace the belt, tensioner, and any noisy idlers together for a long-lasting, quiet fix. (owners.acura.com, gates.com)