Find correct position for center hanger. The general rule of thumb is 1" every 2' (25mm every 600mm) behind center of trailer frame (not including drawbar length). Trailers with more weight to rear will require axle further to rear (e.g. boat trailers/horse floats). When welding hangers to frame, weld along hanger with frame, not across. (welding along frame is stronger)

Find correct center position for middle hanger
Measure from center of drawbar (which should be already fitted) to middle hanger on both sides. Equal distance ensures hanger are square to drawbar.
Measure distance forward and rear of center hangers to suit Eye/Slipper or Eye/Eye configuration springs. Set up according to diagrams and weld hangers into position.
Fit axle location pads to springs.
Remove front spring to fit braked axle, refit springs and centralize axle. (NOTE- lazy axle is approx. 12mm shorter than braked axle when centralizing)
Fit U-bolt and fish plates to braked and lazy axles.
Check square to drawbar on braked axle. Tack weld location pads to axle. Tighten U-bolts. Measure distance from braked axle (which is now square to frame) to rear lazy axle. When distances are the same lazy axle is now square. Tack weld location pads to axle and tighten U bolts. Springs and axles are now assembled to frame.

Assembly Tips for D.I.Y. Kits - Hydraulic Axle Assembly (2.0T Tandem Kit)

--WARNING--

These instructions assume some basic mechanical knowledge and the ability to weld to an acceptable standard. if in doubt please refer the job to qualified personnel.

Pack bearings with grease and fit large inner bearings to hubs and hubdrums.
Fit grease seals to rear of hubs and hubdrums.
Fit hubs to lazy axle. Fit small outer bearings and tighten down castle nut firmly. This ensures bearing cups are pressed firmly into hubs. Back off castle nut until hub is loose, then re-tension until free-play in hub is gone but bearings are under no pre-load (over tightening shortens bearing life)
Fit split pin and dust cap. Lazy axle is now assembled.
Bolt hydraulic brake backing flanges to hydraulic brake backing assemblies.
Slide hydraulic brake assemblies onto braked axle. Note- LH(RL) & RH(RR) orientation. Ensure brake bleeders are to top of axle.
Fit hubdrums to brakes axle with same procedure as steps (3) & (4).
Slide hydraulic brake backing assemblies completely into hubdrum assemblies now fitted onto axle. Mark axle from flange to a point approx. 6mm back. Withdraw brake backing assemblies to this point and use shoe adjustment cam nuts to square up backing assemblies inside hubs. This holds assembled firm and square inside hubdrums for welding.
Weld backing flange to axle (from outside all around), using mig or low hydrogen electrodes.
Back off cam adjustment nuts until hubdrums can be rotated with a slight drag on brake shoes.
Weld 1/4" BSW x 1" long mounting bolts head to rear side of axle approx. 350mm from RH side hydraulic brake backing assembly.
Weld tabs to secure brake lines - 3 to long side and 1 to short side.
Fit 3-way block to mounting bolt.
Fit hydraulic brake adaptors and copper washers to slave cylinders of brake assemblies.
Run long side and short side brake lines in 3/16" bundy tube using short tube nuts and double flare to length as required and fit under tabs welded into position.
Fit flexible brake line to inlet of 3-way block..
Fit brake bleeders. Hydraulic braked axle is now assembled.

Final Assembly

Fit 2.0T hydraulic coupling to drawbar.
Run remaining 3/16" bundy tube from flexible brake line using a double flare and short tube nut up to master cylinder on coupling. Fit off at master cylinder using long tube nut and compression olive.
To bleed brakes, fill master cylinder with brake fluid. Use handbrake assembly on coupling to manually bleed. Bleed long side first (LH side), then short side. No air is present in system when hand brake lever actuator does not "pump up" on repeated operation.

Assembly Tips for D.I.Y Kits (Mechanical Disc Brakes)

--WARNING--

These instructions assume some basic mechanical knowledge and the ability to weld to an acceptable standard. If in doubt please refer the job to qualify personnel.

Pack bearings with grease and fit large inner bearings to hubs and hubdiscs.
Fit grease seals to rear of hubs and hubdiscs.
Fit hubs to lazy axle. Fit small outer bearings and tighten down castle nut firmly. This ensures bearing cups are pressed firmly into hubs. Back off castle nut until hub is loose, then re-tension until free-play in hub is gone but bearings are under no pre-load. (over tightening shortens bearing life)
Fit split pin and dust cap. Lazy axle is now assembled.
Fit Hubdiscs to braked axle with same procedure as steps (3) and (4).
Fit disc brake shoes to mechanical disc brakes assemblies.
Fit disc brake flanges to inner side of disc assemblies using bolts and stainless steel sleeves supplied.
Slide disc assembly over hubdisc and locate disc flange to axle with entire assembly facing what will be the front of the trailer.
Using pad adjusting bolt, clamp disc assembly to hubdisc (this ensures axle flange will be welded square to assembly and hubdiscs)
Position entire disc assembly on stainless steel sleeve so a gap of approx 3mm exists between disc mounting flange and disc assembly. (as brake pads wear, assembly will slide along stainless steel sleeve).
Apply liberal amounts of anti-splatter to hubdisc and cover grease seal with wet rag or PVC tape to protect,.
Before welding disc flange to axle, ensure assembly is lifted as high as it can move on 40mm or 45mm square axle to ensure mechanical lever arm will not foul on spring when fitting under trailer. (not an issue if fitting to 2-1/2" drop axle)
Tack weld flange and unbolt disc assembly. Weld disc flange to axle all around from outside edge and top and bottom end, using mig or low hydrogen electrodes. It is not necessary to weld inner side of flange closets to hubdisc.
Clean antisplatter from hubdiscs using methylated spirits and then refit mechanical disc assembly to hubdisc and rebolt to disc flange. Back off pad adjustment nut to allow approx 12mm movement at end of lever arm before brakes engage. Tighten pad adjustment bolt lock nut.
Mechanical disc brake axle is now assemblied.

FINAL ASSEMBLY

Fit 2.0 Mechanical brake coupling and actuator to drawbar.
Fit cable adjuster to actuator lever on coupling and set for maximum adjustment
Loop 4mm winching cable through actuator lever on mechanical disc brake assemblies and fit 2 off cable clips.
Pull cable through cable adjuster and back to opposite mechanical disc lever checking that cable doesn't foul on spring components etc. Weld half chain links to underside of drawbar and chassis if required for cable routing. Fit cable clips and tension with cable adjuster as required.

Assembly tips for D.I.Y. Kits - Electric Axle Assembly

--WARNING--

These instructions assume some basic mechanical knowledge and the ability to weld to an acceptable standard. If in doubt please refer the job to qualified personnel.

Pack bearings with grease and fit large inner bearings to hubs and hubdrums.
Fit grease seals to rear of hubs and hubdrums.
Fit hubs to lazy axle. Fit small outer bearings and tighten down castle nut firmly. This ensures bearing cups are pressed firmly into hubs. Back off castle nut until hub is loose, then re-tension until free-play in hub is gone but bearings are under no pre-load (over tightening shortens bearing life)
Fit split pin and dust cap. Lazy axle is now assembled.
Bolt electric brake backing flanges to electric brake backing assemblies.
Slide electric brake assemblies onto braked axle. Note LH and RH orientation. Ensure hand brake lever is to top of axle.
Fit hubdrums to braked axle with same procedure as steps (3) and (4).
Slide electric brake backing assemblies completely into hubdrum assemblies now fitted onto axle. Mark axle from flange at a point approx. 6mm back. Withdraw brake backing assemblies to this point and use shoe adjustment cam nuts to square up backing assemblies inside hubs. This holds assemblies firm and square inside hubdrums for welding.
Weld backing flange to axle (from outside all around), using mig or low hydrogen electrodes.
Back off cam adjustment nuts until hubdrums can be rotated with a slight drag on brake shoes. Electric braked axle is now assembled.

Final Assembly

Fit 3.5T electric brake coupling to drawbar.
Fit cable adjuster to handbrake lever on coupling and set for maximum adjustment.
Loop 4mm winching cable through handbrake lever on electric brake assemblies and fit cable clip.
Pull cable through cable adjuster and back to opposite handbrake lever checking that the cable doesn't foul on spring components etc. Weld half chain links to underside of drawbar and chassis if required for cable routing. Fit cable clip and tension with cable adjuster as required.

ASSEMBLY TIPS FOR D.I.Y. KITS (Hydraulic Disc)

(AXLE ASSEMBLY)

-WARNING-

These instructions assume some basic mechanical knowledge & the ability to weld to an acceptable standard. If in doubt please refer the job to qualified personnel.

(1) Pack bearings with grease & fit large inner bearings to hubs & hubdiscs

(2) Fit grease seals to rear of hubs & hubdiscs.

(3) Fit hubs to lazy axle. Fit small outer bearings & tighten down castle nut firmly. This ensures bearing cups are pressed firmly into hubs. Back off castle nut until hub is loose, then re-tension until free-play in hub is gone but bearings are under no pre-load (over tightening shortens bearing life).

(4) Fit split pin & dust cap. Lazy axle is now assembled.

(5) Fit hubdiscs to braked axle with same procedure as steps (3) & (4).

(6) Fit disc brake shoes to hydraulic disc brake assemblies

(7) Fit disc brake flanges to inner side of disc assemblies using bolts & stainless steel sleeves supplied.

(8) Slide disc assembly over hubdisc & locate disc flange to axle with entire assembly facing what will be the front of trailer, with brake bleeder to top of axle.

(9) Hold or clamp caliper assembly so outer brake shoe is hard against hubdisc (this ensures axle flange will be welded square to assembly & hubdiscs).

(10) Position entire disc assembly on stainless steel sleeve so a gap of approx 3mm exists between disc mounting flange & disc assembly. (As brake pads wear, assembly will slide along stainless steel sleeve).

(11) Apply liberal amounts of antispatter to hubdisc & cover grease seal with wet rag or PVC tape to protect.

(12) Tack weld flange & unbolt disc assembly. Weld disc flange to axle all around from outside edge &

top & bottom end, using mig or low hydrogen electrodes. It is not necessary to weld inner side of

flange closest to hubdisc.

(13) Clean antispatter from hubdiscs using methylated spirits & then refit hydraulic disc assembly to hubdisc, apply loctite to mounting bolts & rebolt to disc flange.

(14) Hydraulic disc brake axle is now assembled.

FINAL ASSEMBLY

(1) Fit hydraulic brake coupling to drawbar.

(2) Fit flexible brake hoses to hydraulic calipers ensuring the copper washers are fitted before tightening.

(3) Weld 5/8” washers to convenient location on trailer chassis for fitment of flexible brake line from calipers to body. Ensure sufficient movement on flexible line is available for suspension travel, fit off with hose clips supplied.

(4) Weld head of ¼” BSW x 1” Bolt to location on trailer chassis for fitting of 3 way block. Location

chosen should allow convenient connection of brake line to LH & RH flexible hoses as well as

running of main brake line to back of master cylinder.

( typically the 3 way block is fitted to the RH side inner chassis of trailer )

(5) Tack weld tabs to locations on chassis for brake line routing. (typically ½” flat washer ) lines must

not be allowed excess movement or vibration or working hardening and fractures will result.

(6) Run brake lines from 3 way block to LH & RH flexible hoses. Lines must be fitted off with short

tube nut and double flare both ends.

(7) Run remaining 3/16” bundy tube from 3 way block using a double flare and short nut tube nut up

to master cylinder on coupling. Fit off at master cylinder using long tube nut & compression olive.

(8) To bleed brakes, fill master cylinder with brake fluid. Use handbrake assembly on coupling to

manually bleed. Bleed long side ( LH side ) the short side. No air is present in system when

handbrake lever actuator does not “ pump up “ repeated operation.

Wiring tips for Electric Brakes

--WARNING--

These instructions are a guide only and assume some basic working knowledge of electrical systems. It also assumes tow vehicle has been wired to a standard 7 pin configuration. Not all vehicles are wired to Australian Standards or wired the same. If you do not have the required test tools (or the ability to use them) to find fault problems should they arise, please refer the job to a qualified auto electrician.

It is recommended that at least a 12 gauge (2.5sqmm) 2 core wire is used and run alongside the standard 24 gauge (0.64sqmm) 5 core wire, which is used for lighting applications on trailers. Heavier wire ensures voltage drops do not occur in the system.

One wire from the 2 core flex (typically red) needs to be connected to the trailer electrical plug pin 5 (auxiliary brake).
The other wire (typically black) needs to be connected to trailer electrical plug pin 3 (earth). Earthing faults are generally the most common problem that will occur, so a good earth back to the tow vehicle's earth system is important.
The 2 core wire is then run alongside the 5 core lighting cct wire along (or inside) the drawbar and inside or underneath the body to the braked axle. Allow enough wire for suspension movement when dropping wire from frame to axle.
Connect braked wire (red) to one of the wires protruding from the electric brake assembly. (The magnets can be wired either way so it doesn't matter which one)
At this connection point, run another wire directly across the axle to one of the wires protruding from the electric brake assembly on the other side of the trailer and connect. The power to brake magnets is now complete.
Repeat Steps (4) and (5) for earth (black wire). The earth to brake magnets is now complete. (Wiring for 4 wheel electric brakes follows the same method). It is recommended that the wiring should be run along rear of braked axle, preferably in some sort of protective shroud (e.g. garden hose). This protects against damage to wiring from road debris.
To test brakes, connect trailer to tow vehicle fitted with an electric brake controller. Apply brakes and an audible 'click' should be heard when listening to the braked hubdrum, followed by a constant 'buzz' until the brakes are released. This indicates brake magnets are working.

When towing, set gain on electric controller as per manufacturers directions according to loads being towed, e.g. Heavier loads require higher gain for heavier application of brakes.