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Power To The Max

The Powertrax Acts Like A Spool In A Straight Line Under Power But Unlocks Either Side Around Corners
By Henry De Los Santos, Calin Head
Photography by Henry De Los Santos, Calin Head
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With the cover off and fluid... 
   
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With the cover off and fluid drained, use a 5/16-inch wrench to remove the retaining bolt and shaft.
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In order to remove the limited-slip... 
   
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In order to remove the limited-slip assembly, push in the axles to release the C-clips. Pull the axles about 6 inches out and remove the O-rings.
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Use a thick, flat-head screwdriver... 
   
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Use a thick, flat-head screwdriver to remove the preload spring. This gives access to both spider gears and all the clutches.
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Verify that the gaps in the... 
   
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Verify that the gaps in the coupler teeth are aligned with the gaps in the synchro ring. If not, place the coupler in a vise and use the spacer to align them.
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Once checked, coat a liberal... 
   
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Once checked, coat a liberal amount of wheel-bearing grease onto the driver teeth and spacer. Install it with the widest gap in the ring-gear side outward towards you.
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Coat the saddle springs in... 
   
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Coat the saddle springs in wheel-bearing grease; this will make them less likely to fall out when you place them into the holes of the driver.
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Insert the nonslotted spacer... 
   
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Insert the nonslotted spacer into the nonslotted driver on the ring-gear side first, making sure that the spacer paddle is facing outward.
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Insert the slotted spacer... 
   
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Insert the slotted spacer into the slotted driver and place it in the carrier with the spacer paddle facing out towards you. Then wedge the spacer onto the coupler. The driver teeth should be engaged all the way around.
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The two inner springs need... 
   
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The two inner springs need to be placed inside the two outer springs and compressed into the spring slots. Be sure to visually check the notches by the spring slots. This will show you whether or not the springs are seated correctly. Keeping both drivers wedged in engagement, rotate the unit forward one-half turn to reveal the other spring slot.
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The most crucial step is to... 
   
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The most crucial step is to check the gap between the drivers with the supplied check block. The narrow side of the block should fit, but not the wider side. This will let you know if anything has gone wrong with the install. If the wider side fits, call Powertrax Tech support. If all is well, push the axles back in and replace the C-clips. Lastly, feel through the hole for the pinion shaft and verify that both spacers and drivers are seated correctly. Insert the retaining bolt/roll-pin into the case and tighten the retaining bolt securely.
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At Powertrax’s secret... 
   
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At Powertrax’s secret test facility, the No-Slip system laughed at what we thought were menacing figure-eights and burnouts. Without a doubt, the No-Slip System proved itself worthy and laid rubber down equally from both tires. Going around turns, the No-Slip design unlocked and produced smooth transitions. Simply said…we like!

Nothing is uglier than a one-wheel burn-out, yet so many spend their hard- earned cash ahead of the rear axle without considering how to put the motor’s full power to the ground. In a perfect world, there’d be ultimate traction in all conditions. And on those days at the strip, the traction device would be strong enough to handle gobs of power and deliver it equally to both wheels.

This is why cars that see more track action than street time often run spools.

Spools are strong, but are certainly not user-friendly on the street. Normally going into a turn, one wheel differentiates (turns faster or slower than the other) to allow cornering with ease. With a spool, relatively easy tasks like turning and making U-turns become a nightmare, and driving in bad weather can be deadly.

Most cars on the road today have either an open or limited-slip/posi differential that regulates which wheel gets power. The problem with these designs is that the wrong tire spins in a traction-limited situation. For example, with an open differential, all the power is transmitted to the tire that is spinning. This takes away all the power from the other wheel and doesn’t allow any adequate power to be delivered and propel the car forward. With a limited slip, you get some power transfer to the wheel with the most traction, but the friction materials in the differential quickly wear out with heavy use, rendering the unit useless.

To remedy this, Powertrax developed its No-Slip Traction System, which can be installed with no special tools in less than an hour without resetting your gears, and it’s foolproof. The Powertrax acts like a spool in a straight line under power, locking both axles together, but the design allows it to unlock either side around corners.

You’re only as good as your weakest link, but the smallest of the No-Slip Traction System models can handle 6,800 lb-ft of torque per axle. You do the math; this thing is not going to break. Powertrax makes units for most popular rearends, including 10- and 12-bolt GM axles, and the Ford 9-inch. Follow along as we show you how to install the Powertrax into a Ford 8.8-inch rearend with a limited-slip differential.


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