Wavetrac® At A Glance:

• Innovative:
Patented Wavetrac® design automatically improves grip in low traction conditions. This feature is truly innovative and unlike any other torque biasing diff design.

• Superior Materials:
9310 steel gears run in case-hardened billet or forged steel bodies. ARP® fasteners used throughout.

• Maintenance Free:
As supplied new, the Wavetrac® differential will perform a lifetime of service without maintenance or rebuilds.

Limited LIFETIME Warranty:
All Wavetrac® differentials include a transferable, Limited Lifetime Warranty.

If you appreciate quality, you’ll appreciate Wavetrac®.
You can see it, feel it.

The Wavetrac® is not just good on paper. We build them to last:

• High strength 9310 steel gears
• Case hardened, billet or forged steel housings
• ARP® fasteners throughout.

Our manufacturing tolerances and finish requirements meet or exceed all OEM standards. Wavetrac® differentials are built in American plants operating to ISO9002 and TS16949 standards. Our quality control system checks components at every step as they travel through the manufacturing process.

What makes a Wavetrac® Different?

To best understand how the Wavetrac® is truly different from the other gear differentials on the market, you first have to understand the primary problem that the Wavetrac® solves.

The problem: Loss of drive during zero or near-zero axle-load conditions.

Zero axle-load is a condition that occurs during normal driving, but creates the most noticeable problems when driving in extreme conditions. Zero or near-zero axle-load is the condition that exists when there is ‘no-load’ applied through the drivetrain, when one drive wheel is nearly or completely lifted (often in aggressive cornering). It also occurs during the transition from engine driving a vehicle to engine braking and back, even with both drive wheels firmly on the ground.

Here’s how that loss of drive hurts you:

1) If you lift a wheel, all gear diffs except Wavetrac®, will NOT power the other wheel.

2) During the transition from accel to decel, all gear diffs except Wavetrac®, do nothing.

Why does this happen?

All gear LSDs (including Torsen®, Truetrac®, Quaife®, Peloquin, OBX, etc.) work in basically the same manner: they divide the drive torque between the two axles, applying drive to each side, up to the available grip of each tire. The amount of drive torque one wheel can get over the other is described as the bias ratio, a measure of the torque split across the axle.

Standard, open differentials have a bias ratio of 1:1. They can only apply as much drive torque as there is available traction at one wheel. When one wheel loses grip, the total available drive is lost as well (at a 1:1 ratio). All your power goes out the slipping wheel - along the path of least resistance.

Torque biasing differentials offer increased bias ratios over open differentials. For example, if a diff has a bias ratio of 2.5:1, then it can apply drive torque to the wheel with the most traction (gripping wheel) at 2.5 times the traction limit of the wheel with the least traction (slipping wheel). This is a significant improvement over an open diff… most of the time.

The problem is that when one tire has LITTLE or NO grip (zero axle-load), the other wheel gets ZERO DRIVE, because (basic math here): 2.5 x 0 = 0.

Lift a wheel (or substantially unload a wheel) and you get zero axle-load on that side - that means that during the time the wheel is unloaded, the typical diff will NOT power the wheel that’s still on the ground. No matter how high the bias ratio, you get no power to the ground.

During the transition from accel to decel, where you have near zero torque on the axle, even if the wheels are on the ground, the typical diff is unable to begin applying drive torque until AFTER the zero torque condition is over. While this condition is generally short-lived, the fact that most diffs can do nothing during that time means that there will be a delay once the zero torque condition stops - creating a reaction time in the driveline.

The Wavetrac®, however, is different:


The innovative, patented, Wavetrac® device in the center of the diff responds during these exact conditions when zero or near-zero axle-load occurs. At or near zero axle-load, the axles (and therefore each side gear in the diff) start to turn at different speeds.
This speed differential causes the Wavetrac® device to step into action:

Precisely engineered wave profiles are placed on one side gear and its mating preload hub. As the two side gears rotate relative to each other, each wave surface climbs the other, causing them to move apart.
Very quickly, this creates enough internal load within the Wavetrac® to STOP the zero axle-load condition.

The zero axle-load condition is halted, and the drive torque is applied to the wheel on the ground (the gripping wheel)… keeping the power down.

Some gear differentials rely solely on preload springs to combat loss of drive. The drawback is that you can’t add enough preload to prevent loss of drive without creating tremendous handling and wear problems at the same time. So, to avoid these problems, the preload from ordinary spring packs must be reduced to a level that renders them ineffective at preventing loss of drive. The Wavetrac® is the only differential that can automatically add more load internally when it’s required.

In the case where both wheels are on the ground during zero axle load, such as during a transition to deceleration, the Wavetrac® device is able to prepare the drivetrain for when the zero torque condition stops, eliminating the delay seen with ordinary gear diffs.

What this means for you as a driver is that power is delivered to the gripping wheels for more time and in a more constant manner – making you faster and improving stability.

The Wavetrac® truly is different - and its innovative features can make a real difference in your car’s performance.


Here’s something else you won’t find in any other design:



The Wavetrac® diff’s behavior can be altered in the field to suit your needs. It comes standard with carbon-fiber bias plates for the best all around performance and lifetime durability. Changeable plates using materials with different friction coefficients to fine-tune the bias ratio are sold separately.

These bias plates provide a mechanism to tune the response of the differential as a function of applied torque load. The applied torque load manifests itself as an axial load from the differential pinions into the housing. This axial force is then considered a normal force into the bias plate, and as a function of the effective coefficient of friction, provide a resistive torque to the rotational motion of the differential pinions. The resistive torque will add to the resistance of relative rotation of all components within the differential. The resistive force, however, is non-uniform since it is a function of the axial load from the differential pinions. The unbalance of the resistive torque will manifest as non-uniform energy absorption within the differential causing a bias ratio.


Here are more features that make Wavetrac® even better:


The new Wavetrac® Differential brings current gear technology to the market.

Internally, its gear tooth forms are optimized for strength and improved oil film retention over competitive designs.

Our gear package is smaller, reducing overall mass, yet is more durable since particular attention was paid to the tooth strength - optimized for high torque conditions.

Attention was also paid to the side gear/axle interface, putting as much material thickness as possible in this critical area - most important when power levels get high.

Each Wavetrac® Differential is crafted from the highest quality materials available.

The internal gears are made from high strength 9310 alloy steel.

The diff bodies are machined from case-hardened steel forgings or billet.

To complete the package, every Wavetrac® differential is built exclusively using high quality, high strength fasteners from ARP®, the world leader in fastener technology.

What gear oil should I use?

Your new Wavetrac® differential is incredibly durable and will withstand the harshest environments...as long as suitable oil is used. Many customers ask what oil we recommend for use with the Wavetrac® differential. We feel the best answer is:

Use the "factory fill."

In other words, use the gear oil spec that your car manufacturer recommends for your car. The Wavetrac® is compatible with virtually all factory-installed gear oils used today. If you are racing your vehicle, and wish to upgrade the gear oil to improve performance or durability in racing conditions, choose the oil carefully: be aware that some gear oils have additives that are not recommended for use with your Wavetrac®.

Some have friction modifiers designed for limited slip differentials. These modifiers generally increase slipperiness and are intended to reduce clutch disc chatter in conventional clutch-type LSDs. Some gear oils such as Red Line Oil's Shockproof® type have microscopic solid particles in immersion in order to "cushion" transmission components, acting as an extreme pressure agent. The Wavetrac® and all helical gear differentials in general, operate using friction. The friction generated between its internal gears and its housing are what allow this type of differential to function.

Gear oil additives that drastically reduce friction will actually reduce the performance of gear differentials. The internals of the diff get too slick to generate adequate friction - reducing the differential's effectiveness - reducing its ability to drive both wheels.

In conclusion, when using a Wavetrac®:

  • Use factory spec oils for your car
  • Use Motul Synthetic high performance oils if you wish to upgrade the oil. Please consult Autotech Driveline for recommendations.
  • Avoid gear oils with limited slip additives.
  • Do NOT use RedLine Shockproof® or similar gear oils.

Performance Gear Oils we recommend:

Requirement Oil
75W90 Motul Gear 300 (100118 1l)
75W140 Motul Gear Competition (101161 1l)
Motul Gear Oil is available from Wavetrac dealers


Please note that you will void the Wavetrac® Limited Lifetime Warranty if incorrect gear oil is used.

What kind of horsepower can the Wavetrac handle?

The WAVETRAC differential is engineered to take just about as much horsepower as you can throw at it. In almost any given transmission or rear axle, the WAVETRAC Differential is not the limiting factor in torque capacity. If you have any questions regarding this, please feel free to contact us.

What sort of maintenance is required when using a Wavetrac differential?

There is no additional maintenance required when using the WAVETRAC differential. You can simply install it and "forget" it!

I don't see an application listed for my vehicle, what can I do?

The first thing to do is to check our Facebook page: http://www.fb.com/wavetrac and our site's news page for the latest developments. After that, feel free to contact us. We may have already begun making the Wavetrac you are looking for, but we just haven't publicly announced it yet. Remember, you may not be the only one looking. Many new applications have begun with a single phone call. It would also be a good idea to seek out fellow enthusiast owners that share an interest in the same vehicle. You may be able to gather enough people together to get a small production started.

Give us a call, you got nothing to lose ... and performance to gain!

How do I become a Wavetrac dealer?

Becoming a dealer is very simple. Just contact us, and we will send out a dealer application to you. In most cases, we will get back to you within 48hrs to let you know if your application has been accepted.

What can I do to get Wavetrac to make a custom differential for me?

Autotech is always open to doing special batch runs of differentials, This is one of our specialties. Although a single, custom WAVETRAC differential could be made, it is often cost-prohibitive. A typical, small batch run of differentials is 30-50 units.

What do I do if I think I have a problem with my Wavetrac differential?

The first thing to do would be to call or e-mail us before sending it back to us. One of our trained technicians will gladly help you assess your situation. If at that point, if it is deemed necessary, we will ask you to send us the differential, usually without interfacing parts and bearings. You will need an authorization before returning any items for inspection, service, or repair. We will evaluate your WAVETRAC differential, and advise you of our findings.