Tandem 7k Electric Brake Axle Kit – Slipper Springs – ST235/80R16

Tandem 7K Electric Brake Axle Kit – Slipper Springs – ST235/80R16 (14,000 lb Total Capacity) — Rockwell American

Upgrade your trailer with this heavy-duty Tandem 7K Electric Brake Axle Kit featuring slipper springs and ST235/80R16 tires from Rockwell American (a Dexter company). Designed for precise fitment and smooth tracking on enclosed, equipment, car haulers, utility, and gooseneck trailers.

Includes two axles with brakes, hubs, slipper springs, U-bolt kits, hanger kit, and ST235/80R16 radial tires on 8-lug wheels. Features superior powder-coated finish, Posi-Lube spindles, and continuous bearing lubrication for reduced maintenance. Free Shipping in the Lower 48 states.

Rockwell American trailer axles are made in the USA with a 2-year manufacturer’s warranty, ensuring consistent tolerances and structural integrity for reliable performance.

What’s Included in This Tandem 7K Electric Brake Axle Kit – Slipper Springs – ST235/80R16:

• (2) 7,000 lb Electric Brake Axles with Hubs: Fully assembled with 8 on 6.5 bolt pattern hubs, bearings, seals, races, grease caps, lug nuts, and 12″ x 2″ electric brakes for easy bolt-on installation and reliable stopping power.
• (4) Slipper Springs: High-capacity slipper springs rated at 3,500 lbs each (14,000 lbs total), designed for enhanced durability, smoother rides, and stability in heavy-duty applications.
• (2) U-Bolt Kits: Heavy-duty 9/16″ – 18 x 7″ long U-bolts with plates, washers, and nuts for secure axle mounting.
• (1) Tandem Hanger Kit: Complete hanger set tailored for slipper springs, suitable for 7K axles, boxed for easy assembly.
• (4) ST235/80R16 Radial Tires on Wheels: Radial tires for better handling, longevity, and load support, pre-mounted on wheels for plug-and-play setup.

*Verify hub face, spring center and hub pattern in the options above. Selections may vary to match your trailer’s specs for a custom fit.

Choose Your Axle Size (HF/SC Measurements)

Select the exact hub-face (HF) and spring-center (SC) measurements to match your trailer’s frame width, hanger spacing, and tire/fender clearance. Ensuring safe, stable towing and preventing issues like rubbing or misalignment.

Hub-Face (HF): Measured from the outer face of one hub to the outer face of the other (across the full axle length). Common hub-face sizes range from 61″ to 95″ for standard trailers.

Spring-Center (SC): Measured from the center of one spring seat to the center of the other. This aligns with your trailer’s spring hanger brackets. Typically your spring center is 2″ less then your frame width.

Not sure which hub-face / spring-center (HF/SC) you need? Contact us—we’ll verify your measurements before you order. See our How to Measure a Trailer Axle guide or call (602) 292-9690.

Key Features and Specifications

• Brand: Rockwell American (a Dexter company)—trusted quality with American-made durability.
• Axle Type: Tandem configuration with electric brakes on both axles for superior stopping power and safety on highways.
• Capacity: 14,000 lb total GAWR (7,000 lb per axle) for reliable performance on enclosed, equipment, car haulers, utility, and gooseneck trailers.
• Posi-Lube® Spindles: Enable quick, clean bearing service with grease zerk for reduced maintenance time and continuous protection, ensuring long-term reliability on the road.
• Powder-Coated Axle Tube: Provides superior corrosion resistance against weather and road salt, extending the life of your 7,000 lb electric brake axles in tough conditions. Cambered axle tube for strength and stability.
• Standard 8 on 6.5 Bolt Pattern: 865 (standard; verify with options for your trailer compatibility).
• Cambered axle tube: (3” OD) with underslung, pre-welded spring pads for stable tracking and a lower deck height.
• ST235/80R16 Radial Tires on Wheels: Radial tires for better handling, longevity, and load support, pre-mounted on wheels for plug-and-play setup.
• Technical Components:
  • Spindle Size: #42 with grease zerk for standard 7,000 lb applications.
  • Brake Drum: #8-219-13 Drum / Hub with 9/16″ wheel studs
  • Backing Plates: # 4704-R 12″ x 2″ electric brake, # 4704-L 12″ x 2″ electric brake
  • Inner Bearing: 25580 (1.750″ ID)
  • Outer Bearing: 14125A (1.250″ ID)
  • Inner Race: 25520 (3.265″ OD)
  • Outer Race: 14276 (2.717″ OD)
  • Grease Seal: Part #10-36 (2.250″ ID x 3.376″ OD)
  • Wheel Stud Size: 9/16″

*Verify hub face, spring center and hub pattern in the options above. Selections may vary to match your trailer’s specs for a custom fit.

Documents & How-To Resources

Access these helpful guides and videos to install and maintain your Tandem 7k Electric Brake Axle Kit – Slipper Springs – ST235/80R16 with confidence. Our resources cover everything from axle servicing to brake setup for optimal trailer performance.

Operation & Service Manual — Rockwell American Trailer Axles (PDF): Step-by-step instructions for maintenance, lubrication, and troubleshooting your Rockwell American axle.

Trailer Suspension Diagram & Hanger Kit Spacing (Image): Visual reference for single and tandem axle hanger spacing with double-eye springs—perfect for ensuring proper alignment during installation (adapt for slipper springs as needed).

Johnson Trailer Parts — YouTube How-To Videos: Watch our tutorial videos on trailer assembly, axle replacement, and brake installation for kits like this one.

Frequently Asked Questions (FAQs)

Got questions about the Tandem 7k Electric Brake Axle Kit – Slipper Springs – ST235/80R16? We’ve got answers to help you choose and install with confidence.

Installation Video

Watch this quick video tutorial on installing a similar trailer axle running gear set—get tips on measurements, assembly, and common pitfalls to avoid for a smooth setup.

Questions? We’re Here to Help with Your Trailer Axle Setup

Have questions about the Tandem 7k Electric Brake Axle Kit – Slipper Springs – ST235/80R16? Our experts can confirm your HF/SC measurements, bolt pattern compatibility, and even source custom sizes if needed. Get personalized advice to ensure a perfect fit for your trailer—reach out today for fast, friendly support.

Call (602) 292-9690, email sales@johnsontrailerparts.com, or use our Contact page.