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Synergy Add-A-Leaf Pack for Dodge (06-08) 1500 Mega Cab 4x4, (03-12) 2500, (03-12) 3500 4x4 Trucks

Part #: 8516-XXX
Weight: 149 lbs
  • MSRP: $500.00
Purchase through our Dealer Network.
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  • Weight
    61 lbs
  • SKU
  • Synergy Add-A-Leaf Pack for Dodge (06-08) 1500 Mega Cab 4x4, (03-12) 2500, (03-12) 3500 4x4 Trucks
  • Progressive 5 leaf design replaces the factory overload spring for improved ride quality both on and offroad
  • Eliminates the harsh spring rate ramp up caused by overload engagement
  • High quality 9/16" E-coated U-bolts, F436 extra thick hard washers and GR8 tall nuts included 
  • Bolt on installation using basic hand tools


  • (2) 8516 Add-a-leaf packs (Single or Dual center pin depending on part number)
  • (2 or 4) 1/2-20 UNF x 6.0" long replacement center pins
  • (4) 9/16-18 UNF x 4.0" or 3.50" x 10-11" long HD E-coated U-bolts (Size varies depending on part number)
  • (8) 9/16-18 UNF GR8 tall nuts
  • (8) 9/16" ASTM F436 hard washer extra thick
Part #Description
8516-02-350(06-08) 1500 Mega Cab 4x4, (03-13) 2500, (03-13) 3500 gas engine & 10.5" AAM rear end (3.5" axle tube, dual center pin)
8516-02-400(03-13) 2500, (03-13) 3500 trucks w/ diesel engines & 11.5" AAM rear end (4.0" axle tube, dual center pin)


The installation of this pack will affect the truck's load carrying characteristics when the factory overload is removed.  The owner will notice more "squat" in the rear when carrying heavy loads.  If large loads are frequently hauled, we suggest adding some form of airbag kit in conjunction with this kit for optimum ride and load carrying characteristics.

Installation Instructions

WARNING: Operating, servicing and maintaining a passenger vehicle or off-road vehicle can expose you to chemicals including engine exhaust, carbon monoxide, phthalates, and lead, which are known to the State of California to cause cancer and birth defects or other reproductive harm. To minimize exposure, avoid breathing exhaust, do not idle the engine except as necessary, service your vehicle in a well-ventilated area and wear gloves or wash your hands frequently when servicing your vehicle.
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