Land Rover Drive Belt Tensioner Assembly - Genuine Land Rover ERR6439

Product Information

Accessories such as alternators, power steering pumps, water pumps, and A/C compressors are commonly powered by an accessory drive belt, also sometimes called a serpentine belt. For these to all function correctly, an accessory drive belt tensioner applies the proper amount of tension on the belt to keep it from slipping and ensure the entire system is running smoothly.

There are three main styles of accessory belt tensioners, the most popular being the “Automatic” tensioner. An automatic accessory drive belt tensioner is spring-loaded to maintain constant tension on the belt. Some European cars use a hydraulic-style tensioner, which is slightly more complicated but less prone to bouncing or vibrations if one of the accessories is not in top shape. Finally, a manual accessory drive belt tensioner uses a screw and an arm that needs to be manually adjusted. These are usually found on classic cars and need to be checked as part of regular maintenance.

When an automatic tensioner is failing, you will notice an abnormal amount of bouncing or vibration, usually in conjunction with a bad pulley bearing. Hydraulic tensioners will fail similarly, by losing their ability to damp the vibrations in the system and begin to bounce. Sometimes they can also leak, although the amount of fluid in a hydraulic tensioner is small, so it would be hard to detect. If your belt system is bouncing or wobbling due to slack in the tensioner, replace the tensioner and associated components to do a full belt service.

• Slack in the belt: If the accessory drive belt tensioner is going bad, you will notice the belt bounce and hop due to the inability of the tensioner to apply even constant pressure.
• Pulley Bearing Failure: Many accessory drive belt tensioners have a pulley integrated into the assembly. If the pulley bearing goes bad, it will cause inconsistent or excess resistance on the belt which will inhibit the ability of the tensioner to apply constant tension on the accessory drive belt
• False positives: Occasionally if another component is going bad within the accessory drive belt system, such as a power steering pump or A/C compressor, it can cause intermittent drag on the system that will appear as a faulty belt tensioner. If your belt is not running smoothly, check all the other accessories and idler pulleys to make sure they are smooth.

About Genuine Land Rover

The same parts Land Rover used to build your vehicle are sold as replacement parts under the “Genuine Land Rover” brand. These are manufactured under Land Rover’s direction, guaranteeing top quality. As you’d expect, they also carry a premium price and are sold exclusively through the Land Rover dealership network.

Genuine Land Rover parts trace their origins back to the earliest days of the brand in 1948, when Rover engineers built the first Series I using robust, serviceable components designed for durability in harsh environments. Over the decades, Land Rover established partnerships with leading European suppliers to ensure consistent quality and performance. This tradition continues today, with Genuine Land Rover parts representing the official replacement components engineered to the same specifications as those used on the production line.

What many owners don’t realize is that Land Rover doesn’t manufacture most of these parts themselves. Instead, they design the components, contract trusted suppliers to produce them, and then verify the quality. Many of these suppliers have partnered with Land Rover for decades. In the industry, they’re known as OEMs (Original Equipment Manufacturers)—brands you probably recognize, including Lemforder, ZF, Sachs, Bosch, Valeo, Zimmermann, Siemens VDO, Corteco, and more. It’s not unusual to open a Genuine Land Rover box and find one of these brands inside—just re-badged with a Land Rover logo.

On our site, look for OE tags on product pages to quickly spot parts that come straight from the original manufacturers. Choosing these can save you a significant amount compared to buying them in Genuine packaging. For more details on how to identify OE and OEM parts, check out our OE Academy.