Thank you to all who made Dyno Day special!

🚀 Just Launched - FASS Drop-In Series Diesel Fuel System for Cummins ISX and X15

Monitor your FASS Fuel Filter Life with FASS Connect!
Dynatrac  |  SKU: DT EPJ-80-RARJ-jt

Elite ProRock 80 Rear Axle Roller Jeep JT.

USD 8,10789

Can I pick up my order or have it installed at your shop?

Absolutely. We offer local pickup on most products and full professional installation at our shop in Washington, MO. Whether you just want to grab your parts or have our techs handle the install, we’ve got you covered. Give us a quick call at 636-429-7020 or message us to schedule a visit — we’ll make sure the parts are ready when you arrive.

How do I know if this part fits my vehicle?

Unsure if it’ll fit? No problem — that’s what we’re here for. Send us your vehicle’s year, make, and model, and we’ll verify fitment before you order. We can also point you toward compatible upgrades or supporting parts if needed.

What if I need to return a product or it’s defective?

Most unused items can be returned within 30 days in their original packaging. Some products are covered by a manufacturer’s warranty as well. If something arrives damaged or doesn’t meet your expectations, just let us know — we’ll help you get it replaced, refunded, or repaired. (Tracking updates are also emailed automatically once your order ships.)

What's the lead time on custom or fabricated parts?

Many of our parts are built to order — especially fabricated or performance components. These can take additional time to produce before shipping. Lead times vary by manufacturer and demand, but we’ll always keep you updated along the way. If you’re working on a tight schedule, reach out before ordering at 636-429-7020 and we’ll confirm current availability or estimated ship dates.

Description

Dynatrac

Dynatrac Elite™ ProRock 80 Full-Float Rear Axle

The Dynatrac Elite™ ProRock 80 Axle is built for drivers who demand the absolute highest level of drivetrain strength, durability, and performance. Designed for extreme off-road use and tire sizes ranging from 37 to 44 inches, this axle is intended for experienced drivers tackling the most technical trails and challenging obstacles without compromise.

Engineered from the ground up, the ProRock 80 delivers unmatched rigidity, superior ground clearance, and industry-leading component strength. This axle is ideal for high-horsepower builds, heavy vehicles, and extreme off-road environments where lesser axles simply cannot survive.

Key Features:

  • ProRock 80™ nodular-iron, full-float rear axle housing designed for extreme loads

  • Best-in-class ProRock® ground clearance for 10.25-inch and larger ring gears

  • 4-inch diameter Dynatrac proprietary variable wall thickness chromoly axle tubes

  • 40-spline, full-floating wheel ends with heat-treated 4140 fixed spindles

  • High-capacity wheel bearings with 12-bolt flanged floater hubs and O-ring seals

  • U.S.-made, heat-treated 40-spline 4340 alloy-steel full-floating axle shafts

  • Rock-proof nodular-iron Dynatrac differential cover included

  • CNC laser-cut and fully welded heavy-duty suspension brackets

  • Multiple-position track bar bracket for long-travel suspension tuning

Base Assembly Includes:

  • Dynatrac ProRock 80 roller assembly with differential cover

  • Welded 1/4-inch plate steel mounting brackets

  • Built spindle-to-spindle with wheel hubs and brakes installed

  • Axle shafts not included unless WMS option is selected

Brake System:

  • One-ton OE big brake kit

  • Single-piston calipers

  • 13.88-inch rotors drilled for 8x6.5 bolt pattern

  • Brake backing plates with integrated parking brake shoes

This axle is built to order, allowing customers to configure gearing, lockers, axle width, and additional options to match their specific build requirements. If a desired configuration is not listed, custom estimates are available upon request.

SKU: DT EPJ-80-RARJ-jt

Why Choose FASS Motorsports?

Well worth the price. Quality product. Fast shipping. And great customer service from FASS.
Johnathan Manning
Verified Customer
Product Reviewed
S&S Diesel Gen2.1 CP4 Disaster Prevention Bypass Kit Ford 2011-2025 6.7L Powerstroke
Ordered 1/27 and received 1/28. Couldn’t be happier with quick shipping and awesome customer service.
Josh Holliday
Verified Customer
Product Reviewed
Synergy 03-13 Dodge Ram 1500/2500/3500 4x4 Heavy Duty Tie Rod
FASS Heavy Duty Fuel System purchased and installed at FASS Motorsports. Great product, great service, great people
Robert Vanmeter
Verified Customer
Product Reviewed
FASS Industrial Series Diesel Fuel System Class 8 Semi DD15 290GPH

Also in: