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Eaton Detroit Truetrac LSD - Helical-Gear Limited-Slips

Detroit's Truetrac
By Jerrod Jones
Photography by Jerrod Jones, Courtesy Of The Eaton Corporation
Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Detroit Truetrac
Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Ford Bronco
Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Slip Differential
The Detroit Truetrac is a... 
   
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Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Slip Differential
The Detroit Truetrac is a fully automatic limited-slip differential that works with helical gears instead of clutches or cones. It eliminates any parts that would wear and requires no special LSD additives. There are multiple applications of the Truetrac, and adding an LSD to your axle does not require other parts to be bought.
Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Ring Gear
The ring gear needs to be... 
   
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Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Ring Gear
The ring gear needs to be bolted to the differential and tightened to 65 lb-ft of torque.
Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Hydraulic Press
Next, the guys at Currie Enterprises... 
   
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Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Hydraulic Press
Next, the guys at Currie Enterprises used a hydraulic press to push the bearings onto both sides of the Truetrac diff.
Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Ring Gear Bolts
When the ring-gear bolts were... 
   
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Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Ring Gear Bolts
When the ring-gear bolts were tightened to spec, and the bearings were pressed on, the Truetrac was installed into the 9-inch third member. We did not have to touch the pinion since we were only adding the differential and not changing the ring-and-pinion.
Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Spanner Nuts
Once the Truetrac is in, the... 
   
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Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Spanner Nuts
Once the Truetrac is in, the spanner nuts can be placed as closely as possible to the differential.
Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Bearing Cap
The bearing-cap bolts need... 
   
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Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Bearing Cap
The bearing-cap bolts need to be tightened to 65 lb-ft of torque once they are placed. Remember to use Loctite on the bolts, so they don't back out under load.
Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Backlash
The guys at Currie check the... 
   
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Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Backlash
The guys at Currie check the backlash of every third member that leaves their shop and turn each pinion to make sure the teeth are aligning properly. The spanner nuts on the side of the diff are used to adjust the backlash on the gears. A new ring-and-pinion should have around 10 thousandths backlash between the gears and 15 thousandths if they're used.
Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Gear Pattern
After spinning the pinion... 
   
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Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Gear Pattern
After spinning the pinion and rotating the differential, the gear pattern should show a contact patch (ideally) in the center of each ring-gear tooth. This is an excellent example of an ideal contact pattern.
Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Axlehousing
With the Truetrac installed... 
   
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Lsd Eaton Detroit Truetrac Helical Gear Currie Enterprises Axlehousing
With the Truetrac installed into our third member and ready to go, Currie dropped it into a 9-inch axlehousing to get it ready for some heavy-duty use and abuse.
Currie Enterprises
(714) 528-6957

www.currieenterprises.com
Eaton
800/328-3850

eatonperformance.com

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