FD 8.8 - Complete IRS Kit w/ Grande Axles & Hubs (uses Ford Inner & Outer CVs)
FD 8.8 IRS, Complete Differential Mount Kit w/ Grande Axles & Hubs (ABS optional)
The Grande version of our FD 8.8 here-in is our strongest FD rear end offering. This version requires no donor Mazda parts as both inner and outer CVs are from a Ford Explorer, with Ronin supplied custom hubs to match.
Why run Ford 8.8 diff? It's a powerhouse, substantially stronger than the factory Mazda rear end and is supported by wide range of gear ratios and LSDs. We specifically utilize parts from a 2006-2010 Ford Explorer for their strength, reliability, and availability. Our kit maintains factory like exhaust clearances.
The FD 8.8 Grande Complete Kit includes:
• Front Mount Support Bridge (weld in)
• Rear Mount Diff Ring Cradle (bolt on)
• 4x Mazda Subframe Reinforcement Gussets (weld in)
• 2x Grande Axle Shafts: 4340 heat-treated axle shafts, these feature Ford splines on both ends with a unique length tailored specifically to the FD.
• 2x EMPI CV boot kit 86-2273 (outer CV joints)
• 2x EMPI CV boot kit 86-2215 (inner CV joints)
• 2x CV spacers: ensure proper spacing between the Ford CV and the Mazda knuckle.
• 2x FD Conversion Hubs: built from heat-treated 4340, these hubs utilize full-length splines for maximum engagement. These hubs maintain the original offsets so your existing wheels and brakes all bolt up.
• Extended 2.5" ARP wheel studs pre-installed (Mazda M12 thread pitch)
• 2x new wheel bearings: High-end bearings (Timken, National, or Schaeffler) ensuring reliability and performance.
• 2x Lower Pinion Isolators – up-rated isolators that supports the pinion from below
• All Mounting Hardware – including RTV for resealing the rear cover
• Instructions (hosted online)
Optional (coming soon)
• 2x ABS conversion tone rings. These use the Ford tone ring landing positions but use the FD tooth count. It will relocate the FD sensor slightly to ensure compatibility with your existing ABS system. Note, you'll need either donor Ford outer CVs that were ABS equipped or you can cut a corresponding ABS ring land into non-ABS Ford CVs.
Users Will Source Their Own:
• Ford 8.8" Rear End (2006-2010 Ford Explorer), the complete center section that uses the dual front pinion support.
• Ford 8.8" inner and outer CV joints (from 2002-2010 Ford Explorer axles). Note donor axles must be OEM, not aftermarket or OEM equivalent. Typically this means sourcing used axles from a junkyard or eBay, not just the local parts store. We recommend ABS equipped Ford axles if adding our conversion tone rings.
• A Driveshaft (installation instructions offer various recommendations)
• FD rear diff isolators (your choice of style, but we recommend polyurethane)
A few FD specific notes: The dual front mount for the 2006-2020 Explorer is a stronger load path but the kit is compatible with an Explorer 2002-2005 single front mount diff if required. The FD kit will eliminate the Mazda Power Plant Frame (PPF), so if you’re still running a 13B a dedicated transmission mount will be required. Bonzai’s transmission mount brace is one such option and can function as a stand alone. Our engine subframes and transmission mounts work perfectly for many other combinations.
Performance and Durability
How much power will it hold? We typically recommend the grande version for anyone making 600-1000 hp, as well as for all drag racers and drifters--regardless of power--given they're exceptionally hard on parts. The shafts come with a warranty support program so if you do break one we can get you a replacement at reduced cost (see https://roninspeedworks.com/pages/axle-warranty-support for full details).
Maximize your performance with the Ronin FD 8.8 Grande Complete Kit