About your new Rock
Crawler Shackle Reversal Kit:
FJ40 Front Shackle Reversal:
Remember! Safety First.
This shackle reversal kit was designed to improve the ride
quality and straight line stability of the FJ40 Land Cruiser, yet overcome
certain shortcomings of other shackle reversal kits on the market today.
This system available only through
Man-A-Fre, has a heavier shackle hanger
with more frame contact and closer leaf spring bushing tolerances. Also,
because we rotate our springs, keeping the short side or "fixed" side
forward at the new "fixed" position, you will gain an additional five
degrees of approach guide. Other brands of shackle reversal kits actually
reduce your approach angle as much as eight degrees.
Installation of this kit should not be attempted by the non-mechanically
inclined, or those of you without access to a few tools. You will benefit
greatly from the use of an angle grinder, electric drill, a pair of C-clamps
and a big hammer. Four bolt holes are provided in each of the four brackets
for those doubtful ones who wish to test this kit before making the
commitment of welding the kit on. Because bolts have a nasty tendency to
work loose at the most inopportune time, please weld this kit on. Do not
rely on the integrity of the bolts to protect your life or your Land
Cruiser! If you are not a competent welder either have the kit installed by
someone who is or bolt the kit on and drive it to a shop as soon as possible
to have it welded.
This kit was designed around the stock shackle length. Approximately two
degrees of caster will result with the installation of this kit. This will
improve your straight line stability and on highway manners. Because your
shackles will now be at the rear of the spring, every increase in shackle
length will result in an increase in caster. Oversize shackles will result
in excessive caster. This may drop the differential's pinion shaft too low
creating angles too severe for your u-joints at full drop. If you feel a
need to run long shackles, consult a front end specialist with a good
knowledge of four wheel drives. It can be done properly but will probably
require rotating the spring pads on the housing.
The installation of this kit will afford 1-1/4" to 1-1/2" of lift. If used
in conjunction with after market lifted springs, it may require a driveline
modification. If you seem unsure, ask a driveline shop mechanic. Their
advise may save you a big towing bill.
Bump stops spacers have been provided. Whether needed depends greatly on the
vehicle and it's accessories. Combined with lifted springs, the increased
wheel travel may exceed the range of any stock located shocks. Bump stop
spacers will limit upward travel allowing you to go with a shock having
greater droop or extended length but a shorter collapsed length. With stock
springs and an entirely stock setup, you shouldn't need the spacers.
1. Remove bumper and its
pertaining hardware. (tow hooks, triangular plates, etc.)
2. Raise front of vehicle with jack high enough to remove weight front the
3. Place jack stands in a safe location behind the front leaf spring mounts
leaving yourself ample room to work around the spring mounts.
4. Remove shackles, U-bolts, spring pins and remove the leaf springs. Note
which end is the forward end.
5. Remove the shackle hangers and spring hangers from the frame by grinding
off the rivets, drilling part way through their centers, then driving them
through the frame with a drift pin or punch. The forward shackle hangers
will also require grinding of four one-inch welds per side.
6. Remove the two triangular bumper mounts by removing the two rivets that
secure each to the frame.
7. Align the spring hangers supplied in the kit on the outside of the frame
horns flush with the front of the frame (angled side forward). The holes
drilled in the hangers should line up approximately with the factory rivet
holes. Weld the hangers in place. Secure the bumper mounts back to their
original location with the 7/16" bolts washers and lock nuts provided. In
some cases, it may be necessary to run a drill bit through the mounting
holes for alignment.
8. Shackle hangers should be installed with 42-1/8" from the center of the
forward spring pin hole to the center of the pin hole of the shackle hanger.
The holes, provided for bolts in the event the installer has no access to a
welder, can be filled with a weld. Weld the hangers in place.
9. Install new bushings.
10. Now you may need to replace the stock leaf spring center bolts with
those provided in the kit in order to accommodate caster shims. To safely
remove the stock bolts, place a C-clamp on each side of the center bolt
leaving yourself room to access the bolt with a wrench. Tightening the
clamps allows you to remove the bolt easily and safely.
11. Install the new bolts. These have a longer head and should allow you to
reference the hole in the axle perches with caster shims in place.
12. Rotate the leaf springs so the front (long side) is now rearward. This
insures the long side, or flex side originally coupled to the shackle
remains coupled to the shackle as it was originally engineered to be.
13. Re-install the leaf springs with the supplied caster shims, thick side
to the rear.
14. Re-install the bumper. The mounting holes in the bumper will need to be
15. Now that you are finished, jack up the truck from the bumper to maximum
droop. Be sure there is adequate spline engagement on the driveshaft.
FJ55 and FJ60 Series Front Shackle
About the kit:
Because of the similarities
of the FJ55 and FJ60, the 4+Plus shackle reversal kit will accommodate
either vehicle. The spring hangers in this kit have been equipped with a
dual bolt pattern thus enabling use on either model.
This kit will account for approximately 1.5" of lift up front and may
require longer rear shackles to level the cruiser. Since each vehicle rides
unique to itself, depending on what accessories or passenger number is
typical, we suggest installing the front kit and trim the rear height to
When used in conjunction with our Man-A-Fre lifted springs and rear
shackles, you should expect about 3.5" to 4" lift and 3" additional wheel
travel, although more is quite common especially in the case where the stock
springs sagged out. You will also inherit a safer approach as you will no
longer need to concern yourself with shackle inversion when you drive into
those immovable obstacles.
As with any lift, it is recommended that after your final shock selection is
in place, elevate the vehicle to allow full axle droop and note whether
driveshaft modifications will be necessary.
1. Raise the cruiser and
support it with quality jack stands. Remember, during re-assembly, the
reversal kit will add 1.5" of lift so leave enough room under the tires at
full droop to allow easy re-assembly.
2. Remove the front springs and shackles and place them out of the way. Now
would be a good time to inspect the U-bolts. If they are in good shape, they
can be re-used. Otherwise, you should probably acquire others before trying
to put this cruiser back together at 6 p.m. Sunday night after the parts
3. Remove the front bumper and using grinders, torches, punches or whatever
destructive devices in your arsenal, remove the four frame rivets at each
bumper bracket and set the brackets aside.
4. Take the spring hangers supplied in your kit and using the 7/16" hardware
supplied, install the spring hangers sandwiching them between the frame and
the original bumper brackets. We strongly recommend welding these in
place! If you don't have the capability, after the install is complete
make arrangements to have someone do it for you.
5. The shackles are design to fit at the rear within the stock spring
hangers using the stock spring pin so no guessing or measuring is required.
6. Now you may re-install your leaf springs with the caster shims supplied.
The thick side of the shim goes to the rear. Remember to torque the u-bolts
95-105 ft. lbs. should do nicely.
7. Re-install your bumper. If you purchased new shocks install them now.
Man-A-Fre can recommend which shocks will serve you best according to the
suspension package you've purchased.
8. Now you should raise the front of your cruiser allowing full droop. Spin
the front driveshaft by hand checking for u-joint bind. Check the driveshaft
for adequate spline engagement. If you're unsure in either case, seek a
second opinion. If all looks good, go drive over a Jeep or something.