The best rear you will find for the GTO!

GTO (2004-06) M9 Housing, Axles (up to 35 spline), Chrome Moly Torque Arm, Chrome Moly Cross-member, Control Arms, Sway Bar, Panhard Bar, QA1 double adjustable shocks, Springs, Driveshaft Loop and all associated mounting hardware.

 This same combination has given us a 1.29 60ft in our Camaro with M/T 225/50R15 dot drag radials, so we know this system works!

The Moser M9 weighs the same as the spindly GM late model 7.5" 10 bolt, yet this rear is very strong!

The front crossmember is designed to be easily welded to the chassis. 

Moser incorporated a driveshaft safety loop into the transmission crossmember.

Shown is the front multi adjustable mounting point for the torque arm.
The torque arm can telescope back and forth just behind the front mount, which prevents any possibility of binding.

The Moser lower control arms can be seen in these two pictures.

Adjustable lower control arm relocation brackets come as standard equipment with our Moser M9 rear.

The Moser supplied adjustable panhard bar is shown towards the top of the picture. The oil fill for the Moser M9 rear can also be seen towards the top of the housing.

Hal/QA1 double adjustable shocks and springs are supplied with these rears.

The Moser anti roll bar is shown in this picture. This anti roll bar should only be used for very limited street use, and is the hot ticket for launching straight off the starting line.

Shown are the double mounting points at the rear for the chrome moly torque arm.

You can supply your own center section, or the rear can be ordered with a Moser center section. See the options for center sections.

TRAC-LOC LIMITED SLIP
The Trac-Loc Limited Slip Differential is designed as a direct replacement for the hard to find expensive OEM unit, or for those enthusiasts desiring to convert to a limited slip. Available for 9” Ford rear ends, this nodular steel casting is totally rebuildable, includes nickel steel side gears and pinion gears, and multiple plate 360-degree steel clutches. This extremely tough and durable differential houses 400-ft/lb static springs, and is capable of 150 lb. braking torque. Available in 28 or 31 spline. Made in the U.S.A.

DETROIT LOCKERS
Moser Engineering carries a full line of Detroit Lockers to fit most popular rear ends used on the street, off-road, or on the racetrack. Detroit Lockers are fully automatic locking traction differentials, manufactured by Tractech, a well-known manufacturer of heavy-duty traction differentials for OEM and replacement applications. A Detroit Locker maximizes the available traction by delivering 100% of the torque and power to both drive wheels. It is engineered to keep both wheels in a constant drive mode, yet has the ability to unlock to permit the wheel to turn at different speeds if necessary.

Wavetrac® At A Glance: • Innovative: Patent pending 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 steel bodies. ARP® fasteners used throughout. • Maintenance Free: As supplied new, the Wavetrac® differential will perform a lifetime of service without maintenance or rebuilds. • Customizable: If desired, you can alter the diff’s behavior to suit your needs using optional components. • Limited LIFETIME Warranty: All Wavetrac® differentials include a transferable, Limited Lifetime Warranty.

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, patent-pending, 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 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.

 

MOSER STEEL SPOOLS
Need to upgrade to a true performance spool? We carry a complete line of full spools for most race applications. By changing your carrier to a Moser performance spool, not only will you save weight, but you will also enhance the performance of your car. In addition to performing better, the life of your rear end will increase by reducing deflection in your case and eliminating the possibility of side gear failure. All Moser spools are heat-treated and precision machined. Moser spools are available for most popular rear ends including 10 & 12 bolts, 8.8” and 9” Ford, 8 ” Chrysler, and Dana 60. Moser spools are available in most popular spline counts and our steel spools carry a lifetime warranty to the original purchaser.

This is what a GTO would look like with the exact same tires we use on our Camaro. 225/50R15 M/T dot drag radials, although these are mounted on Centerline 15 x 10 wheels.

This is page 96 from the Feb 2010 issue of GM High-Tech Performance magazine.