Are you using the correct alternator pulley?

Take a look at that replacement alternator ? Could it ruin your customer relationship?

Millions of vehicles are now factory-equipped with an Overrunning Alternator Decoupler (OAD) rather than a conventional solid pulley or one-way clutch pulley. A failure to install the correct replacement design could cause severe damage to a vehicle's belt drive system.

An OAD Decoupler is similar in appearance to other pulley designs but plays a vital role in synchronizing the belt drive system. When replacing an OAD-equipped alternator, the only acceptable choice is another OAD unit.

When working with any pulley or belt tensioner for a late-model vehicle, always replace Original Equipment (OE) design with OE design. After all, your reputation is at stake.

Many new vehicle accessory drives are realizing a 1.5% to 2% fuel economy improvement with a Litens OAD.  These improvements are possible by utilizing Litens' Lean System design philosophy.  Lean systems, with only Litens' OAD, can significantly reduce the common parisitic losses found in accessory drives, due to the belt bending that occurs during operation.  The parisitic loss reduction is a result of a holistic approach to accessory drive - drive layout, OAD, and tensioner design/matching.

 
Solid Pulley vs. OAP (One-Way Clutch) vs. OAD

This comparison of three leading alternator pulley designs demonstrates the danger of using the wrong type of pulley on a vehicle requiring an OAD decoupler.

Note the severe level of belt drive vibration (see whiplashing belt tensioner) when a SOLID PULLEY is installed on the belt drive system.

Similarly, the use of an "OAP" (ONE-WAY CLUTCH) on this application also results in significant belt drive vibration, causing NVH issues and wear of key components.

This footage shows a Litens OAD DECOUPLER on the same application. Note the smooth, efficient, low-stress operation of the belt drive system.

Alternator Pulley Comparison

This video demonstrates the excessive levels of NVH, belt system stress and other severe issues resulting from the use of a SOLID ALTERNATOR PULLEY on this Ford engine.

This clip shows the use of a variety of ONE-WAY CLUTCH alternator pulleys on the same engine.

Now we see the smooth, efficient operation of the same engine belt drive system using an OAD decoupler pulley (also known as a Litens IDP "Isolating Decoupler Pulley"). The Litens OAD/IDP was previously marketed under the RotorRX brand.

Solid Alternator Pulley Demonstration

This engine requires an overrunning alternator decoupler (OAD) pulley. To show the importance of using the right pulley design, we installed an alternator equipped with a SOLID PULLEY.

Notice the severe vibration in the belt drive system. This condition will cause a loss of engine efficiency/fuel economy, shortened belt and bearing life, extreme NVH, and other problems.

One-Way Clutch (OAP) Demo

This is a closeup view of the belt tensioner on a vehicle equipped with the wrong alternator pulley design - a "one-way clutch" (overrunning alternator pulley, or OAP). This engine requires an overrunning alternator decoupler (OAD).

Note the significant vibration and stress on the belt tensioner. This condition will likely lead to unsatisfactory levels of NVH and reduced component life.

Litens OAD Closeup

This tight view of an alternator equipped with a Litens overrunning alternator decoupler (OAD/IDP) shows how the patented spring-loaded mechanism absorbs belt drive vibration.

This innovative design - required on millions of vehicles - boosts engine efficiency and helps eliminate NVH issues.

It is never appropriate to use another alternator pulley design in place of an OAD/IDP on vehicles originally equipped with this technology.

This video was created using a strobe light to see how the OAD pulley compensates and absorbs the engine pulses being transmitted by the belt to the alternator rotor.

Benefits of OAD Pulleys

Several vehicle manufacturers now specify overrunning alternator decoupler (OAD) pulleys - also called IDP pulleys - for their latest engines due to the extremely smooth, efficient belt drive performance made possible by this technology.

It is never appropriate to use another alternator pulley design in place of an OAD/IDP on vehicles originally equipped with this technology.

Vehicle Makes/Models Requiring Decouplers
  • Chevrolet Cobalt   • Chevrolet Corvette   • Chevrolet Malibu   • Chrysler Pacifica   • Chrysler Sebring   • Dodge Caliber   • Dodge Caravan   • Dodge Prowler   • Jeep Compass   • Jeep Liberty KJ   • Jeep Patriot   • John Deere 4.5L Tractor   • Lexus GS   • Lexus IS   • Lexus ES   • Pontiac G6   • Pontiac Solstice   • Pontiac Vibe   • Saab 9-3   • Saab 9-5   • Saturn Ion (Redline)   • Saturn Sky   • Toyota Avalon   • Toyota Camry   • Toyota Corolla   • Toyota Matrix   • Toyota RAV4   • Toyota Sienna   • Toyota Solara   • Volvo V70   • Volvo XC90   • Volvo S80