Instructions - Offset Rack Drop Kit (2020 Onwards Isuzu D-max/MU-X and Mazda BT-50 - 4JJ3) Posted on 1 Dec 16:37

Installation Guide:

The installation of this Offset Rack Drop Kit requires good mechanical knowledge and tools. It is important to follow these instructions.

N.B: Be very careful when working underneath your vehicle, ensure you are correctly using jack stands or the hoist locks if working on a hoist. Ensure the Ignition is switched off for at least 30 seconds before disconnecting any wiring connections.

Munji Recommended Wheel Alignment Specs:

  1. Caster: +3 Degrees LH & RH
  2. Camber: 0 Degrees LH & RH
  3. Toe: +0.5mm LH & RH - Total +1mm


  • 32mm, 22mm Spanner
  • Socket Set
  • Ratchet with long and short extension
  • Flat Screwdriver
  • Pliers/Adjustable Pliers
  • Silicone 
  • Mallet/Hammer
  • Razor Blade/Stanley Knife for bush removal


  1. Ensure ignition has been switched off for at least 30 seconds prior to beginning the install, and that the steering is pointed straight ahead with the steering wheel locked in place. Begin by removing the bash plates underneath the vehicle. 
  2. Remove the clamps holding the rack end boots on using a flat screw driver for the larger inner clamp, and a pair of pliers for the smaller outer clamp. Slide the boot all the way down to the end of the rack end as shown.
  3. Remove both rack ends from the steering rack using a 36mm spanner or adjustable pliers. Unthread completely and carefully rest the rack ends on the Lower Control Arm.
  4. Looking the RH Front wheel, carefully mark the spline connection for the steering shaft with a paint pen or similar. Ensure it is a neat mark so you can accurately line the spline up after. Remove the 12mm locking bolt and carefully wiggle the two halves of the steering shaft until the splines separate.  
  5. Remove the 1x bolt holding the rear diff mount to crossmember, and the 1x bolt holding the RH side diff mount to chassis. Carefully lower the RH side of the diff and push backwards to gain more room.
  6. Remove the 2x wiring connectors to steering rack and move wiring out of the way. Remove the 4x 22mm Bolts holding the rack to the chassis. The Top 2x Rack bolts have nuts behind the mounting brackets that need to be held. Some of the bolts will need to stay with the rack as there isn't enough room to slide them out. The top LH bolt is best accessed through LH wheel arch, while the remining three bolts and wiring connections from underneath the vehicle. The red arrows below point to the Steering Rack mounts.
  7. Carefully lower the rack down, being mindful of the steering shaft as it has to snake through the engine mount. The diff will need to be pushed back slightly on the RH side to have clearance to remove it. 
  8. Once the rack is out of the vehicle, the bushes will need to be removed. We did this by using a cylinder with an internal diameter of ~45mm and height of ~50mm, a fully threaded 110mm long M10 bolt, some washers and a nut. Use the bolt to pull the bush out of the rack into the cylinder. Alternatively, you can try cut the lip of the bush off and smack them through with a hammer. Take utmost care not to damage the rack. Munji has removal tool kits coming soon which will make this job a breeze.
  9. Once the bushes have been removed, you can fit the Munji Offset Bushes into each mount on the rack. Fit them from the back of the rack forward, so the side of the bush without the collar is against the chassis. Using the Blue Alignment tool, sit it on the side of the bush without the collar and line the hole up in the bush with the relevant hole in the alignment tool. For the two upper rack mounts, use the hole marked TOP MOUNTS, and for the lower two rack mounts use the hole marked BOTTOM MOUNTS. Spin the bush and alignment tool together until the 'fingers' of the alignment tool match up with the rack webbing, then mark with a paint pen or similar from the collar of the bush to the rack. Now, you can remove the alignment tool and bush, apply a bead of silicone around the bush as pictured and refit it, lining up the marks you just made. Once the bush is in, fit the nylon crush washer over the side of the bush without the collar, pressing it on firmly. It will hold the bush in place while the silicone sets. Double check the bush is aligned with the marks and repeat for the remaining 3 mounts.
  10. Once the Munji Offset Bushes have been fitted, you can remove the large diameter washers from the 4x Rack bolts and swap them for the smaller diameter high tensile washer provided.
  11. You can now carefully refit the Steering rack to the vehicle. Ensure you fit the bolts that had to come out together with the rack before you fit the rack to the car. Also take care to not apply too much twisting force to the bushes to prevent them from moving. Loosely fit all 4x Rack bolts before tightening them up.
  12. The two electrical connectors can be refitted to the rack. Be sure to 'click' them together to prevent any issues arising.
  13. Refit the RH and Rear diff mount bolts and tighten up. Be sure to check none of the vacuum lines to the diff have been pulled off during the install. 
  14. The steering shaft can now be refitted, being sure to re-align the marks you have made on the splines so the steering wheel remains aligned. Refit and retighten locking bolt.
  15. The rack ends can also be refitted and tightened, along with the rack boots. The factory inner boot clamps can be swapped for the provided stainless steel zip ties to make refitting the boots easier. Use a flat screwdriver against the head of the clamp whilst pulling the band tight with pliers to achieve a strong grab.
  16. The bash plates can now be refitted and a wheel alignment carried out. That's it, your done!

If you have any issues please contact me and I am more than happy to assist.
All the best with your 4weeling. Stay safe.