A Guide to the Serpentine Belt for the 2016-2017 Lexus IS300
Understand the signs of a failing serpentine belt and how to choose the right aftermarket replacement for your Lexus.
- Focus on the 2016-2017 model years for the IS300, as earlier years were different models.
- Squealing noises and visible cracks are the clearest signs that a replacement is needed.
- When replacing the belt, always inspect the tensioner and idler pulleys for noise or roughness and replace them if they are not perfectly smooth.
- Premium aftermarket brands like Gates and Continental offer OEM-level quality and are trusted choices for this vehicle.
Is Your Lexus IS300 Serpentine Belt Failing?
A serpentine belt is a wear-and-tear item. It is made of durable rubber, but over time, the engine's heat and constant friction will cause it to degrade. Ignoring the warning signs can lead to a sudden breakdown. A broken belt will cause an immediate loss of power steering, stop the battery from charging, and can lead to rapid engine overheating. Here are the common symptoms that your belt needs attention:
- Squealing or Chirping Noises: This is the most common sign. A high-pitched squeal, especially when you start the car or accelerate, often means the belt is slipping.
- Visible Wear: Pop the hood and look at the belt. If you see cracks, frayed edges, missing ribs, or a shiny, glazed appearance, it's time for a replacement.
- Accessory Problems: If your headlights seem dim, the A/C isn't blowing cold, or the steering feels heavy, the belt may not be providing enough power to those components.
- Warning Lights: A battery warning light on your dashboard can indicate the alternator is no longer being spun by the belt.
Known Issues, Recalls, or TSBs
For the 2016-2017 Lexus IS300, there are no widespread serpentine belt issues, recalls, or Technical Service Bulletins (TSBs) on record with the NHTSA. Searches found major recalls for a fuel pump issue on these models, but that problem is unrelated to the belt drive system. Premature belt failure is more commonly linked to a worn-out belt tensioner or misaligned pulley rather than a defect in the belt itself.
Pro Tip: Check the Tensioner and Pulleys
The serpentine belt system includes a spring-loaded tensioner and one or more idler pulleys that guide the belt. These components have bearings that can wear out. When replacing your belt, it is critical to spin each pulley by hand (with the old belt removed). They should spin smoothly and silently. If you feel any roughness or hear any noise, the pulley should be replaced. A failing tensioner is a primary cause of belt problems, so many mechanics recommend replacing the tensioner assembly at the same time as the belt, 🎬 See how to replace the belt tensioner on this engine type. especially on higher-mileage vehicles.
Choosing the Right Aftermarket Serpentine Belt
The original Lexus belt is a high-quality part, often made by manufacturers like Bando or Mitsuboshi. However, top-tier aftermarket brands offer similar or even superior quality, often at a better price. Here’s how the available brands generally stack up based on owner feedback and mechanic consensus:
- Premium Brands (OEM Quality or Better): Gates and Continental are consistently regarded as top choices for Lexus vehicles. They are known for their durability and quiet operation. Many professionals consider them to be equivalent to the original part.
- Standard Brands (Reliable Value): Dayco is a well-respected brand that offers a great balance of quality and affordability. It's a solid choice for owners looking for a reliable replacement without the premium price tag.
- OEM-Supplier Brands: INA is a major manufacturer of belt tensioners and pulleys for many car brands, including some OEM parts for Lexus. While they also make belts, they are more known for their high-quality drive system components. A kit from another brand may even include an INA tensioner.
Ultimately, you cannot go wrong with any of these four brands. Failures are rare when the belt is installed correctly on a system with a healthy tensioner and pulleys.
| Part Type | Estimated Cost |
|---|---|
| New Aftermarket Belt | $41.87 - $65.66 |
| New OEM Belt | $45 - $65 |
| Shop Labor | $77 - $113 |
| Total Professional Replacement (Aftermarket) | $119 - $179 |
Frequently Asked Questions
Why does this guide cover 2016-2017 instead of 2012-2017?
The "IS300" model name was introduced to the North American market starting in the 2016 model year as part of the third-generation IS platform. Earlier models from 2012-2015 were the IS250 and IS350, which may use different parts. This guide is specific to the 2016-2017 IS300 with the 3.5L V6 engine.
🎬 Watch this walkthrough of a belt replacement on a similar Lexus V6.Can I replace the serpentine belt myself?
Yes, this is a DIY-friendly job for those with basic mechanical skills. The process involves relieving the tension on the belt tensioner with a wrench, removing the old belt, routing the new one correctly, and releasing the tensioner. The most common mistake is routing the belt incorrectly, so taking a picture or finding a diagram for your 🎬 Watch a professional demonstrate the removal and replacement process. 3.5L V6 engine is essential.
How often should the serpentine belt be replaced?
Lexus recommends inspecting the belt at regular intervals (like every 60,000 miles), but there is no strict replacement schedule. A good rule of thumb is to replace it based on condition or between 60,000 and 100,000 miles as a preventative measure.
Should I buy a belt and tensioner kit?
If your vehicle has over 75,000 miles or if the tensioner has never been changed, buying a kit that includes the belt, tensioner, and any idler pulleys is a smart investment. The labor to replace these parts is nearly the same, and doing it all at once prevents the old tensioner from causing premature wear on your new belt.
Helpful Videos
Technical Specifications
OEM Part Numbers: 99367-K1550 90916-A2026 99367C1550
Belt Type: V-Ribbed (Serpentine) Rib Count: 7 Approximate Length: 1550mm Common Part Number Structure: 7PK1550
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.
- Lexus IS300: