INSTALLATION INSTRUCTIONS
Integral Disc Brake

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debris or grease, and inspect the bearing surfaces and threads for
damage. Carefully inspect the original brake flange for straightness
and any weld spatter or imperfections that will affect proper
mounting of the brake caliper later (Fig. 1).

CAUTION

• Failure to properly secure or support the trailer weight while
servicing could result in serious injury or death. Make certain all
lifting and supporting equipment has sufficient capacity, is used
properly, and the trailer is securely supported on jack stands.

For 3,500 lbs. disc brake kits, proceed to step 7. For 5,200 lbs. and
6,000 lbs. disc brake kits, proceed to step 6.

• A “disc brake ready” actuator must be used with these brakes.
Actuators designed for drum brakes will cause disc brakes to
work improperly, quickly overheat, and fail, resulting in property
damage, serious injury, or death.

6.

5,200 lbs. and 6,000 lbs. disc
Figure 2
brakes kits will come with a brake
flange adapter plate (Fig. 2). Install
the brake flange adapter plate
onto the existing axle brake flange,
with bent legs of the bracket facing
out towards the axle wheel end.
The adapter plate mounts with five
Brake
3/8”-24 UNF bolts, nuts, and lock
Flange
Adapter
Plate
washers. Install medium grade
(blue) Loctite® 242 or equivalent on the threads and torque the
bolts/nuts evenly in a star pattern to 35 ft. lbs..

7.

Remove the hub & rotor from its packaging. If it came with the
bearings installed and pre-greased, be careful not to let the outer
bearing fall out of the hub & rotor when installing it. If bearings
were not installed, wipe the hub & rotor bearing cups with a
clean cloth, lubricate the inside bearing cone and cup and install
the bearing, then press the rear seal flush with the machined
top of the seal cavity on the rear of the hub & rotor per the axle
manufacturer’s instructions. If not otherwise specified by the axle
manufacturer, use a NLGI #2 boat trailer wheel bearing grease and
fully work it into all the bearing rollers and cups. Wipe a thin coat
of the lubricant on the rubber seal inner lip. Lubricate the spindle
bearing journals and lightly lubricate the seal journal. Slide the hub
& rotor carefully onto the spindle with a slight rotation to guide
the inner bearing cone and seal over the spindle threads, bearing
journals, and the seal journal without nicking the seal lip. Lubricate
the outer bearing cone and cup and install the cone, along with the
original spindle washer and nut, and finger tighten the nut.

8.

Use a wrench to tighten the spindle nut to 50 ft. lbs. torque,
continuously rotating the hub & rotor slowly while tightening the
nut. If a torque wrench is not available, use a 12” long wrench with
hand force. The bearings should bind, but not lock up. If they lock
up, investigate and repair as required.
Leave the hub & rotor stationary and slowly loosen the wrench just
until the torque on the nut goes to zero. Be ready, the torque will
typically go to zero suddenly; don’t loosen past that point.

• Ensure the brake hydraulic system is properly bled and
functioning properly in order to assure adequate braking
performance for safe trailer operation.
• Ensure the caliper mounting fasteners and spindle nut are
tightened to the specifications below to avoid a caliper locking a
wheel, losing braking function, and/or loss of a wheel resulting
in a loss of control, property damage, injury or death.
1.

Jack up trailer and secure on adequate capacity jack stands.
Follow trailer manufacturer’s recommendations for lifting and
supporting the unit. Use the jack only to lift the trailer, never for
support when servicing. Always fully support the trailer with jack
stands, all around; and block the trailer to keep it from rolling,
moving, or falling off the stands when being serviced.

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CAUTION

Do not lift or support the trailer on any part of the axle or
suspension system. Never go under any trailer unless it is
properly supported on jack stands which have been rated for
the load. Improperly supported vehicles can fall unexpectedly
and cause serious injury or death.
2.

Remove the tire and wheel assembly.

3.

Remove the existing dust cap or bearing protector by carefully
prying it off progressively, or gently tapping it to the side with a
mallet as the hub or hub & drum is rotated by hand.

4.

Remove the existing hub or hub & drum, retain the existing spindle
nut, washer, and any nut retaining hardware. Discard used cotter
pins, bearings, and seal that came with the original hub.

9.

Remove any existing drum
brake backing plates and
rigid brake lines that were
connected, and cap the
brake line(s) temporarily.
Clean the axle spindle of

10. While rotating hub & rotor, finger tighten the spindle nut as
the critical final bearing adjustment step. Install any spindle
nut retainers or a new cotter pin per the axle manufacturer’s
instructions. If necessary, move the nut to install the pin or retainer;

5.

Figure 1

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Brake Flange

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loosen the nut only as much as necessary, never tighten the nut
beyond finger tight (Fig. 3 & 4). If the axle manufacturer has
different bearing assembly instructions than above, follow them.
Figure 3

15. Install the trailer wheel and ensure
the wheel inside has clearance to
the brake caliper body as it rotates.
Tighten all lug nuts in a star pattern
with an accurate torque wrench to
the torque specified by the trailer
manufacturer (Fig. 6).

Figure 4

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Figure 6

CAUTION

When finished with the installation, torque the wheel nuts to the
trailer manufacturer’s specifications. Re-torque nuts again at 10,
25, and 50 miles to avoid a possible wheel separation, which can
result in property damage, serious injury, or death.

11. If the axle has an E-Z Lube® or similar style spindle with the grease
fitting installed, properly lubricate the bearings at this time, and reinstall the dust cap. If the axle has a pressurized bearing protector,
such as a Trailer Buddy, install it using a block of wood and mallet.
Add grease through the fitting until the protector’s piston just rocks
or is in the middle of its travel.

16. Road test the trailer in a safe
location. After the first few stops,
check the brake fluid in the
actuator reservoir and top off
again to the proper level. Note:
brake performance may not be
optimum until the brake pads
adjust and seat themselves to
the rotor. If braking performance
still needs improvement, repeat
the brake bleeding procedure to
resolve.

12. Inspect the caliper ensuring that the brake pads are properly
installed. The brake pad friction material faces towards the rotor
and seats into anchor points and against the caliper piston. Slide
the caliper over the rotor and attach the caliper to the brake flange
or brake flange adapter plate. The caliper bleeder screw should be
oriented to the top, and caliper fluid inlet to the bottom. Typically,
the caliper will be mounted with the caliper body/piston and brake
lines towards the rear of the axle.
13. Make sure the caliper bleeder screw is facing upward when bolting
on the caliper (Fig. 5). Start the
Figure 5
two 7/16”-20 UNF caliper bolts
through the brake flange or
adapter plate into the caliper yoke
with medium (blue) Loctite® 242
or equivalent. Install and torque
the bolts to 55 ft. lbs.. Ensure the
hub & rotor will rotate inside the
installed caliper with sufficient
clearance and no more than a
Bleeder
slight contact with the brake
Screw
pads, or adjust caliper/pad
clearances as required to allow
hub & rotor rotation.

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Figure 7

CAUTION

Before road testing, make sure the area is clear of vehicular
and pedestrian traffic. Failure to brake safely could result in an
accident and personal injury to yourself and/or others.
Additional resources are available at www.dexteraxle.com.

14. Use a brake hose with a male 3/16” inverted flare fitting to
connect to the caliper with enough flexibility to allow the caliper to
move at least 1/2” as the brake pads wear. Tighten the brake line
fitting into the brass banjo inlet on the caliper just snug enough
not to leak. Reference torque: Only 6 to 7 ft. lbs. or finger tight +
1/2 turn on the brake line. The 5/8” head banjo bolt and fitting is
torqued to 30-35 ft.-lbs.; no tighter or the hollow banjo bolt may
strip the threads. Connect and secure all brake lines appropriately
for the trailer’s intended use. Ensure that the caliper and brake
inlet line have sufficient clearance to the trailer frame and
suspension to avoid contact under any loading scenario. Fill the
brake system with new DOT 3 fluid (or if these are replacement
brakes, a different fluid may have been specified by the trailer
manufacturer in very rare cases; confirm compatible fluid for
those) and bleed per the brake actuator manufacturer’s
instructions. Use a clear bottle with hose at the caliper bleed ports
so one can absolutely verify all air bubbles are removed from the
system when bleeding.
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