Isuzu CALMINI Shackle Lift

Nov. 01, 2005 By Randy Burleson
All Isuzu light trucks use compression-type shackles (the frame is above the shackle, which is above the spring). CALMINI Manufacturing makes an excellent extended shackle that replaces the stock shackle.

Remember that you are only changing the height of one end of the spring, and that the middle of the spring is where the axlehousing mounts, so two inches of additional shackle length only amounts to about one inch of actual lift between the wheels and the frame. CALMINI's longer shackles don't change the spring rate, so they won't change the ride much -- though grease-able bushings can improve ride slightly. Longer shackles give cheap and easy lift, and may increase travel.

Installation

Follow these steps to install CALMINI's lift shackles:

  1. Chock the front wheels securely.

  2. Jack up your truck until the rear wheels are well clear of the ground.

  3. Use jack stands to secure the truck's frame.

  4. Position your jack's lifting pad under one set of u-bolts.

  5. Undo the nut that holds the bolt which connects the leaf and the shackle.

  6. Jack the axle up far enough to unweight the spring at the shackle but not so far that you compress the spring. If done just right, the spring eye bolt will be loose enough to pull out by hand. You can use a pry bar to move the spring up and down a bit, but its easier to just set the right height with the jack. If you can't quite get the bolt out by hand, use a centerpunch and a hammer to drive the bolt out.

  7. The shackle should now be connected to the truck only at the frame. Remove that connecting bolt and set aside the old shackle.

  8. If you are replacing bushings, you'll have to remove the old ones, which can be nearly impossible. You can upgrade to grease-able polyurethane bushings. Rubber bushings can be more compliant than urethane bushings, but are susceptible to dry rot and oil contamination when exposed to gas, oil, or grease. For more information, please view another excellent Off-Road.com article on polyurethane bushings.

    • If you are lucky, a hammer and screwdriver will be sufficient persuasion. You won't be that lucky.

    • I've pressed a handful out successfully with a C-clamp and a couple of sockets. If you can take the springs fully off the vehicle, a bench vise also works.

    • If these fail, then burn them out with a torch. This is a smelly, nasty mess, but works almost every time. Adequate ventilation is a must -- and don't drip molten rubber on concrete you care about.

    • Some bushings are vulcanized to an outer metal sleeve which must be cut and pounded out.

    • When the bushings are out, use emery cloth to clean any left over rubber or metal fragments out of the spring eye.

    • If you are using polyurethane replacement bushings, be sure to grease them up with the manufacturer-provided grease or regular heavy bearing grease. You may need to use the C-clamp (or bench vise) and sockets to force the new bushings into the spring and frame eyes.

  9. Loosely bolt the new CALMINI shackle to the frame hangar, using CALMINI's supplied bolt and nylock nut.

  10. Lower the axle down far enough to line up the spring and the longer shackle. If you get it exactly right, you'll be able to insert the spring eye bolt by hand. As noted above, you can use a prybar to move the spring up and down a little, but it is far easier to set the right height with the jack. If you can't quite get the bolt in by hand, use a hammer to gently drive the bolt across the shackle and through the bushing. Be careful not to munge the threads.

  11. Tighten the shackle bolts until the nuts just touch the shackle side plates. Do not overtighten these fasteners.

  12. Lower the axle with the jack until the wheels are back on the ground and the truck's weight is fully on the spring and shackle assembly.

  13. Tighten the shackle bolts to the recommended torque. This torque should be enough to sandwich the bushing firmly between the shackle and spring but not pinch it. Pinching the bushings can shorten their life and interfere with normal suspension travel. Since CALMINI provides nylock nuts, you can keep them a little less tight, and get a little more travel. Too much play can lead to sloppy handling and axle-steer.

  14. Repeat the above steps on the opposite side of the vehicle.

  15. Jack up the truck, remove the jack stands, and lower the truck.

Things to Check

After the CALMINI shackles are on, you might want to check a few things. None of these issues will be a problem if you use CALMINI's lift shackles which are engineered for your Isuzu light truck, but it never hurts to check for:

  • Suspension travel and frame interference with the longer shackles.

  • Check for too-short brake lines, emergency brake cables, or differential vent lines with the suspension at full droop travel.

  • Check also to make sure your shocks are not limiting travel. Off-Road.com has an excellent shock fitment guide.

Lifting one end of the leaf does change the suspension geometry, drive line angle, and pinion angle. Drive with caution until you are confident that these effects are minimal

Larger Tires?

With so many different tire sizes available, you'll have to measure and carefully plan what will fit on YOUR truck. I ran 33's on my Amigo with a CALMINI shackle lift and tweaked torsion bars, and I had only minor rubbing on the rear inner wheelwells and at the backs of the front wheelwells.

Sources

  • CALMINI's shackle kit provides the shackles and new shackle bolts. If you want to use polyurethane bushings, Energy Suspension carries them. Contact CALMINI at: CALMINI Manufacturing, Isuzu ORC Department, 6951 McDivitt Dr, Bakersfield, CA 93313 U.S.A. Phone: 1-800-345-3305 Fax 805-398-9555 For more information email CALMINI.

  • Energy Suspension carries polyurethane bushings for Isuzu products. Contact them at: Energy Suspension, Department Isuzu ORC, 1131 Via Callejon, San Clemente, CA 92673. Sales: 1-714-361-3935.

  • Daystar Products carries shackle bushings for Isuzus, and though they have yet to put together a grease-able kit, they have all the parts required to source the grease-able bolts and bushings. Daystar does not sell directly to the public, but Accessories Plus carries their line of products. Contact them at 1-800-729-4294.

  • If you don't mind using Toyota bushings, the shackle bushings for the 1979-85 pickup trucks fit the Isuzu spring and frame eyes. Northwest Off-Road Specialties (NWOR) carries grease-able bushings and bolts for Toyotas. Contact NWOR at: Northwest Off-Road Specialties, ORC Isuzu Department, P.O. Box 1617, Bellingham, WA 98227-1617. Phone (360) 676-1200 or FAX (360) 676-5401.

Please mail the Isuzu ORC Staff if you have questions or comments about this page.


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