Dave Thornton takes a look at how the wheels, tyres and brakes of his trailer have fared since a refurbishment eight years ago.
When I purchased my second-hand Formula 233 back in early 2004, it was obvious we’d need to do a full rebuild of the trailer’s running gear. In fact, everything had to go! The trailer was originally a triple-axle rig with 14” galvanised steel rims running normal car tyres, however, all the brakes had been disconnected. Not only that, the springs were rusted – one had even broken in half – the pivot pins were seized and so it was all pretty unsafe.
Obviously, I’d need to do some serious TLC if I even attempted to tow this boat!
Certainly, when you move up into the 2000kg towing category the braking requirements and laws change. By law you have to have brakes on all wheels plus a ‘breakaway system’ to pull the rig up and hold it stopped if it detaches from the trailer.
When you move up to 3500kg you are at the maximum capacity of all large 4WDs and the difference between the earlier category and heavy big rigs really show up in the towing and stopping abilities.
It amazes me the number of imported boats you see that don’t have the correct towball coupling, or braking set-up. In Australia we use a 50mm, or a larger 70mm towball. Yet many imported trailers don’t have approved breakaway system and many actually have a tow coupling that is slightly larger than 50mm so it is possible for these to come off!
Being in control is vital when you are towing a boat, especially a big rig. You can get into serious trouble if you don’t have sufficient braking power, or blow a tyre. That’s why I’ve gone for good quality gear. Especially with triple-axle rigs they’re included to go straight ahead, and are harder to turn. For this reason I replaced the under carriage springs with AlKo axles that allows the rig to sit lower. AlKo is the market leader when it comes to heavy, independent suspension in boat trailers.
For my trailer AlKo recommended the galvanised 2500kg axle with six stud LandCruiser hubs and Trojan stainless steel brake calipers. The hubs feature large, tapered roller bearings and huge solid steel disc brake rotors. The brakes are activated by the Sensabrake breakaway unit, which is also an AlKo product.
Heavy duty tyres: The next decision was to fit heavy duty tyres on reliable rims. Tyres are a really important item on a trailer and are often overlooked by boat owners. How many times do you see trailer boats beside the road with a blown tyre? I see a lot around holiday time, and that’s why I went for decent tyres on the trailer.
I picked Performance Wheels, which have a large range of alloy trailer wheels in all stud patterns and sizes. Performance supplies many of Australia’s top trailer manufacturers so they’re the best people to talk to. They suggested 16 x 6 inch white five-spoke rims rated at 1250kg with a silver trim band and chrome hub covers.
To keep everything attached to the road I chose Bridgestone Dueler 693 215/65/R16 104R light truck tyres. No point having great suspension and brakes if the tyres can’t grip the road.
The technology for the modern tyre has come a long way and these Duelers feature a two-ply carcass, which enhances casing strength for excellent resistance to road hazard damage. Two steel belts provide high levels of durability, plus a full spiral cap means the body of the tyre is reinforced with a spiral cap layer of nylon. This design provides maximum resistance to puncturing while the stiffer construction enhances manoeuvrability and handling. Stronger side walls also mean these tyres are less likely to flex and suffer sidewall damage when turning tight corners.
The Dueler A/T D693 is a superb all-rounder and is as tough as they come, which makes it the perfect choice for a heavy rig.
When you want to buy tyres the first thing you need to do is learn to read the details on the sidewall of the tyre. Have a look at the numbers and that will give you all the information you need to find a replacement or even decide if you have the correct rating.
The numbers displayed will read the width, the profile, followed by the construction type and rim size. The last bit of information is the maximum load and the speed rating.
The Bridgestone Duelers are 215mm wide. The profile is the height of the tyre from the rim to the tread area. It’s displayed as a percentage of the tread width so in my case the profile of the tyre is 65 per cent of the width, so the height of my tyre is 140mm high.
The construction type is R, which stands for Radial Ply; almost all car tyres are radial. In the past there was bias ply or cross ply constructions and you needed to identify the different types of tyre because you could not have mixed types on the same axle. If there is no ‘R’, the tyre is not a radial.
The last number is the diameter of the actual rim that the tyre is designed to fit, so mine are 16-inch diameter. After these numbers there may be another number and letter, these are the load rating so 104 equals 950kg and the R is speed rated to 170kph.
On most tyre manufacturers websites you’ll find this information so spend some time researching before buying. Avoid retreads at all cost because they tend to delaminate and blow out easily. Also, always try to buy tubeless tyres because when you tow a long distance the tyre heats up from the rubber inner tube rubbing against the inside of the tyre.
Wear and tear: So how has the refurbish rig fared after eight years on the road and many trips? Well, let’s start with the tyres themselves. In fact, the wear and tear has been fantastic. They have worn evenly and have no splits or cracks in the sidewalls.
One of my tyres had a slow leak from a nail in it, so I took it off and had it repaired. Other than that I have had a trouble-free run and will certainly use Duelers again when it comes time to replace one.
The rims on the trailer are powder coated alloy rims that started off looking great, but now look tired. The inner chrome cap rusted after 12 months and the saltwater caused corrosion that soon got under the powder coating and it began to peel off.
If I was looking at rims for a trailer that went into saltwater I doubt I would choose powder coated again, they will all suffer the same fate as the powder coating is damaged when you tighten up the wheel nuts. Galvanised steel rims or just plain alloy are probably a better option for the long-term and would be cheaper to buy.
The Trojan disc brake calipers are made of stainless steel and are as good today as the day they were fitted. I’ve taken these brakes off many times for maintenance and only need to re-grease the slide pins with copper grease and crack the brass bleed screw once a year when I bleed the brakes.
I found I need to change the brake pads every two years, but that became a yearly event as I travel a lot. However, recently I’ve found that the pads are wearing out more quickly and this is caused by the rusting of the brake disc rotor. The rusted surface of the brake rotor simply tore into the pad material and this wears them out quickly. I’ve tried different anti-rust products but the rust always wins.
Most of the damage starts when you launch the boat and the trailer sits in the sun all day with the salt drying in the sun. Most of us only wash the brakes down at the end of the day but the damage is already done.
If the trailer is going to be left sitting without use for long periods then I spray them with a 50/50 mix of linseed oil and mineral turps from a garden spray pump. This helps to slow down the rusting.
Regular maintenance: I have removed the whole hub assembly many times to replace the wheel bearings and have machined the disc rotors three times in eight years to remove the rust and create a smooth surface.
Not many brake shops will machine rusty rotors for trailers as it can damage the brake lathe tips, but as tips are only a few dollars each it should not be a problem, however, it will take twice as long to get a nice surface on a rusty rotor so expect to be charged more. Around $20 to $30 a disc would be fair. Recently, I removed the hubs and replaced the actual rotors, these are designed to be replaced but you need to be careful. Depending on what type of hub set-up you have, changing the disc rotors is an easy task. On my trailer I first removed the hub assembly from the stub axle and laid the whole hub on a sturdy bench. The disc rotors mount behind the hub and the wheel studs then come through the rotors into the hub, so I needed to knock the wheel studs out. The best way is to use a hydraulic press but as most of you don’t have one and I didn’t have one at home, I simply used a big hammer!
But there is a right and a wrong way to do it, first get a spare wheel nut and put it onto the stud you plan to remove, wind it all the way down until the flat surface of the wheel nut is almost level with the end of the stud (see pic). Using a heavy hammer that has a fair amount of weight in it, hit the wheel nut square on top. Start off using the hammer's weight and don’t belt it too hard, increase the force with each blow and you will find that the stud comes out.
Before you hit anything, make sure you have some safety glasses on so that no metal fragments can hit you in the eye.
Once you have the wheel studs removed you can knock the hub from the disc rotor. I used a metal wire wheel to clean any rust on the hub before I placed the new disc rotor on it. Then I added some grease to the wheel studs and simply hammered them back into place through the back of the rotor. The hub was checked and re-greased if needed and refitted to the trailer. Next, I fitted new brake pads to the caliper and refitted the caliper to the axle.
Replacing the pads: If you need to replace the brake pads on your trailer it is a very easy job, just remove the wheel, remove the caliper from the axle and remove the worn pads. You will need to push the caliper piston back to allow the new pads to be fitted, the easy way is to undo the cap from the fluid reservoir on the trailer actuator and put an old brake pad over the piston in the caliper, then you place a G-clamp as seen in the picture here and gently wind the piston back into the caliper.
Only ever remove one caliper at a time so that you don’t pop the pistons out from the other calipers, always do one wheel at a time. Once the piston is wound back, make sure the two parts of the caliper body slide into each other and you can easily pull them apart, if the floating part of the caliper gets stuck then the brakes may not release correctly, use brake cleaner in a can to wash the sliding pins and re-grease with copper grease or lithium based wheel bearing grease. I find that this type of work is best done a month before the season starts and that you check the wheel bearings at the same time.
Wheel bearings can be checked by first raising the wheel off the ground and spinning it. If it makes a rolling audible noise, then remove the hub and check for faulty bearings.
Next, wipe the grease away and check the roller bearings for any rust marks or pitting. Signs of overheating show up like as a change of colour in the bearings – similar to a light blue tinge. This indicates they need replacing.
When you remove the bearing caps have a look at the grease colour and see if any water droplets come out. I have found that lithium-based grease is better that soap-based grease because it repels water better. The soap-based grease tends to absorbthe water and change the grease to a different colour and often a thinner appearance, while lithium-based grease stays the same colour but you see the water droplets.
I will soon be changing to oil-filled hubs and will do a full report and evaluation on them in a later issue.
Regular tests and checks: At the start of each season I make it a routine event to check the trailer from top to bottom – looking for damaged winch cables or stripped gears, faulty lights or any other running gear faults.
The tyres on the trailer should be inspected for uneven wear and remember to look for any bulges in the tread. This often indicates a nail has made its way into the tyre and hasn’t been repaired. Water soon gets into the puncture and causes the steel belts to rust in that spot.
The rusting causes bulging of the tread that leads to its delamination. Left untreated it can lead to a blowout.
If you find any cuts or splitting in the sidewall of the tyre then replace it, when we look at the roadworthy items on a car, any damage to a sidewall is a fail. Also keep the tyres at the correct pressure, you would be amazed at how much a tyre actually flexes on the road when you are towing.
On my rig I run 42lb of pressure cold, this increases as the tyre gets hot on a long trip. When you tow the trailer, find the time to stop and feel the tyre and the hub to get a feel for heat. If it feels warm to the touch then it’s all good, but if it feels quite hot then you have a problem that will only get worse. It could be a bearing issue or it could be the brake calipers sticking or holding. As your brakes apply the heat generated by the friction is transmitted into the hub and then also into the rim and tyre. The heat quickly dissipates as the brakes release, however, if the caliper sticks on and doesn’t release then the heat eventually leads to bearing failure and also causes excess drag on the transmission in you towing vehicle.
When we travel on a long trip from home we always carry a spares kit in the car. The kit contains an inner and outer trailer bearing kit, a rear hub seal, spare bearing caps, split pins, a set of brake pads and a tub of wheel bearing grease. The tools include a large pin punch, large shifter and a hammer plus rags and rubber gloves. So, if we do suffer a blown bearing, I can repair it on the side of the road and get us out of trouble.
If you aren’t mechanically minded or not confident about doing these type of roadside repairs then join the RACV or NRMA so that if you do break down you can get help. If you at least carried the parts with you, then I am sure the roadside assistance would be able to help fix it for you.
Sensible brakes: The Sensabrake unit has been fantastic. The concept of this unit is fantastic and it uses compressed air to activate the hydraulic pressure required to operate the calipers. If the trailer detaches the unit will apply the brakes and hold the trailer for over 15 minutes. This meets all requirements for trailers over 2000kg and there is no trailer mounted battery, just the unit mounted on the trailer.
The amount of force required is determined by the brake controller fitted to the car. I did have fluid leakage problem but not until the unit was four years old. Now these units are manufactured and tested to Australia these problems are sorted. You can send the units back for repairs and it is all done in Australia.
The latest Sensabrakes can be controlled from a common under-dash type electric brake controller rather than the dedicated EvoV controller, however, personally I prefer the dedicated controller. I have fitted other brand brake actuators but I would definitely stick with the AlKo Sensabrake unit on any future trailer. I believe it’s the best system available on the market today.