Accessory Drive Belt Guide for the 2003-2012 INFINITI FX35
Keep your FX35 running smoothly by understanding its accessory drive belt system and choosing the right replacement parts.
- 2003-2008 FX35 models use two belts with manual tensioners; 2009-2012 models use one belt with an automatic tensioner.
- Squealing on startup is the most common sign of a worn or improperly tensioned belt.
- Bando and Mitsuboshi are excellent aftermarket brands that are likely the original OEM suppliers for INFINITI.
- If your FX35 has high mileage, it's wise to replace the tensioners and idler pulleys along with the belt(s).
Understanding Your FX35's Belt System: Two Generations
The 2003-2012 INFINITI FX35 spans two different engine designs, which affects the accessory belt setup. It's the most common mistake owners make when ordering parts.
- 2003-2008 (S50 Generation): These models use the VQ35DE engine. This engine typically has two separate accessory belts: a main belt for the alternator and power steering, and a second belt for the A/C compressor. These systems use a manual tensioner, which requires loosening a lock nut on the pulley and turning an adjustment bolt to set the correct tension. 🎬 Watch this walkthrough for replacing belts on the VQ35DE engine.
- 2009-2012 (S51 Generation): These models use the updated VQ35HR engine. This engine uses a single serpentine belt for all accessories. It is equipped with a spring-loaded automatic tensioner, which simplifies belt replacement as no tension adjustments are needed. 🎬 See how to easily replace the single belt on 2009-2012 models.
Is an Aftermarket Belt Good Enough for My INFINITI?
Yes, high-quality aftermarket belts are an excellent choice for the FX35. Many Japanese vehicles, including INFINITI, use belts from manufacturers like Bando and Mitsuboshi as original equipment (OEM). This means you can often buy a belt from one of these brands and get the same quality as the dealer part, but for a lower price.
- Top Tier (OEM-Equivalent): Bando and Mitsuboshi are highly regarded and are likely the original suppliers for INFINITI. They are known for their durability and precise fit, making them a top choice for replacement.
- Excellent Aftermarket: ACDelco is a well-respected brand that offers reliable, high-performance belts suitable for the FX35. While not an OEM supplier for INFINITI, their products are a dependable alternative.
Estimated Replacement Costs for INFINITI FX35
| Part/Service | Estimated Cost |
|---|---|
| New Aftermarket Belt(s) | $17 - $58 |
| Shop Labor | $78 - $114 |
| Total Professional Replacement | $95 - $172 (Parts + Labor) |
Frequently Asked Questions (FAQ)
How do I know if my FX35 has one belt or two?
If your FX35 is a 2003-2008 model, it almost certainly has two belts. If it is a 2009-2012 model, it has a single belt. This is the most important factor when buying a replacement.
My belt only squeals when I turn the A/C on. What does that mean?
For 2003-2008 models, this is a classic sign that the separate, smaller A/C belt is worn or loose, or its manual tensioner needs adjustment. The main drive belt is likely fine.
Are there any recalls for the FX35 accessory belt?
No. Searches of the National Highway Traffic Safety Administration (NHTSA) database show no recalls or technical service bulletins (TSBs) specifically related to the accessory drive belts on the 2003-2012 INFINITI FX35.
How often should the accessory drive belt be replaced?
Accessory drive belts are a wear item. It's recommended to visually inspect the belt(s) starting around 40,000 miles for any signs of cracking, fraying, or glazing. Many owner's manuals suggest replacement around 60,000 miles as preventative maintenance.
Helpful Videos
Technical Specifications
OEM Part Numbers: 11720-AG900 11720-4P102 11720-JK20A 11720-1CA1C 11720-4P10A 11720-EY00A 11720-EY00B
First Generation (2003-2008, VQ35DE Engine) uses a two-belt system with manual tensioners. Second Generation (2009-2012, VQ35HR Engine) uses a single-belt system with an automatic tensioner.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- INFINITI FX35: