Trailer Tech: Spring has Sprung Checklist

Welcome back to Trailer Tech!

The snow is melting and the days are getting warmer. Spring is here and it’s time to get back on the road. With the weather improving, now is the perfect time to perform some maintenance and any necessary modifications to your trailer to get ready for spring and summer road trips. During our performance voyages and other road trips, we made some observations on the checks needed to keep our trailer running smoothly.

GENERAL TIPS

• Begin with a basic visual check and make sure everything on your trailer is in good working order. An obvious tip perhaps, but it can be easy to not pay enough attention to this step. This includes anything that actuates or illuminates
• Assess the general condition of the axle
• Grease the axle bearing nipples or repack your bearings to keep them running cool and smooth. Check with your axle manufacturer for model specific maintenance requirements
• Check for wear and proper impedance on electric brake magnets. Magnets that test outside of the manufacturer specified impedance should be replaced
• Remember that you will need marine-grade grease for boat trailers backing in and out of the water up and down boat ramps
• Check brake hydraulics (if equipped) for leaks. Change the hydraulic fluid per the manufacturer's recommended schedule. Ensure the parking brake and breakaway cables are not frayed or properly connected
• Check brakes for uneven wear or scoring, proper mounting and ensure proper actuation. If the brake pads or shoes are approaching the linings, they should be replaced

• Check the lug nut torque and ensure that your wheels are not falling off! Apply a thin layer of anti-seize to the studs
• Check the tires for bulges, cuts, nails and heavy/uneven wear
• Tire pressure checks reduce tire wear and the use of nitrogen will result in lessened loss of pressure over time

• Prevent corrosion with rust inhibitor products and touch up paint. Remember that a little bit goes a long way! Thick applications of rocker guard, rust inhibitor, undercoat, anti-seize and paint allows moisture to build up over time and rust the underlying component.

SUSPENSION

• Water has the unique characteristic of expanding when changing from a liquid to a solid state, and during a freeze thaw cycle, moisture in between the leaves in a leaf spring pack can loosen and shift the leaves. Even if your trailer sat idle for most of the winter, it is important to check that the leaf pack is tight and straight and that the spring clips are free of rust and tight.
• Some springs require additional attention during maintenance in the shackle and bushing departments due to comparatively higher complexity when mounting. Many modern double eye springs use a nylon, bronze, or polyurethane bushing. Worn bushings will appear frayed or cracked towards the outer edges and become worn down and thin towards the center, developing groves from wear. Bronze bushings require wet bolts that need to be greased.
• Applying a thin layer of grease anywhere there is contact between shackle straps and spring hangers ensures the spring can flex freely without binding.
• Check spring seats shackle straps and hangers for cracks in the welds that secure them to the frame or axle. Check for bends and deformations and excessive wear around bolt holes. Replace as necessary and prevent corrosion with rust inhibitor products and touch up paint.
• Ensure shock absorbers provide adequate resistance, and replace if they feel loose or leaky. Ensure shock absorber and rubberized equalizer bushings are pliable and are not cracked or hard.

U-BOLTS/TIE PLATES

• During installation, U-bolts should be torqued down only once. Reusing them reduces clamping force by 55%.
• Torque should be checked/re-checked after road-testing and some use. If your leaf spring pack, leaves, or Trailer Blocks have shifted, your U-bolt torque may be incorrect and should be checked.
• Always ensure they are SAE-Grade 8 with rolled thread
• Prevent corrosion with a thin layer of anti-seize on U-bolt threads. This can help to facilitate re-torque. Use a thin application of rust inhibitor on tie plates and U-bolt arms as needed.
• Read our blog about Reusing Tie Plates | Trailer Blocks: bit.ly/2Vpr9xI 

We hope the tips outlined thus far have been helpful in guiding your seasonal checks in a effective way. It is important to remember that your trailer may have special or varying equipment that needs additional maintenance and checking. Always consult your owner’s manual for exacting recommendations. If you are not mechanically inclined or equipped to carry out the seasonal checks you should consult a qualified mechanic with experience working on trailers.

If you feel we’ve missed anything or would like to add to the discussion, please leave a comment below or contact us at contact@trailerblocks.com if you have a question for us specifically.

Thanks for reading.

Trailer Tech: Damping Trailer Suspension

Welcome back to Trailer Tech. We’ve all experienced jarring suspension and dangerous bumping at some point in our lives, so today we’re taking a look at the role shock absorbers play in improving the ride quality, handling, braking, and stability of your trailer. Trailers encounter the same road imperfections that cars do and, without damping, can pass them on to the cargo and the tow vehicle in the form of front to back chucking, side to side swaying, wheel hop, vibration, bouncing, bucking and jolting.

The bumps one feels while travelling down the road have a certain unbalanced cadence that can be measured and reported as a frequency. Suspension systems and dampers work together to absorb these imperfections and provide a smooth and safe ride. While suspension systems absorb imperfections in the road, they are only storing the kinetic energy in the form of suspension movement. Shock absorbers are a type of damper that absorb the kinetic energy from the spring and then dissipate that energy. Shock absorbers have to cope with road conditions that can both impact and oscillate the suspension.

The type of shock absorber used varies based on the type of trailer suspension since different types handle shock differently. For example, the friction between the leaves in leaf spring suspension provides some damping which results in little low frequency oscillation which is good. However, if the road conditions get severe, leaf springs struggle to provide good ride quality as bumps that produce excessive suspension movement also result in a jarring and bumpy ride. Depending on design and loading conditions, leaf spring suspension can also suffer from high frequency vibrations. As a comparison, torsion axles tend to provide good absorption of severe bumps and vibrations but can settle into an oscillating rhythm without proper damping. These are just a couple of situations that highlight the importance of selecting the type of shock absorber best suited to your application.

Now, let’s take a look at the shock absorber and damping options commonly available for trailer suspension and where they provide the most improvement.

Leaf spring suspensions can benefit from rubber bump stops or rubber springs. Bump stops will simply prevent the axle and suspension from impacting the frame, providing severe shock absorption while rubber springs can help support the trailer’s load and provide bump stop and damping functionality. Bump stops and rubber springs are generally mounted to the trailer’s frame directly above the axle. Tandem axle and triple axle leaf spring suspensions benefit from rubberized equalizers which absorb severe bumps and high frequency vibrations, improve ride quality and braking and reduce chucking. These equalizers generally replace the standard solid equalizer and offer quick bolt-on installation. Air bag versions of the rubberized equalizer also exist generally offering more sophistication and tuning capability.

All suspension systems benefit from the use of hydraulic tube shock absorbers to control suspension oscillation. Trailers specifically suffering from oscillation such as those equipped with torsion axles or anyone wishing to improve their trailer's handling characteristics achieve the most noticeable results from this type of damping system. Controlling oscillation improves vehicle ride quality, stability, control and handling. Choosing the right amount of damping is important as too much will cause the trailer to bump and jolt while not enough provides no improvement. For this reason, hydraulic shock absorbers are set-to and sold-by a specific weight range.

Mounting of hydraulic tube shocks may not be straightforward as both the angle and position of the shock absorber is important. For example: in leaf spring suspension, the tube style hydraulic shock absorber should be mounted as close to the wheel it is controlling as possible and on the side of the axle closest to the spring shackles to absorb the most movement. It can be mounted vertically to absorb suspension movement alone, angled back not more than 20 degrees if absorbing braking forces is also required or inward not more than 20 degrees if absorbing body roll is required. This varies from torsion axles' need to control oscillation where, dependent on space restrictions, the mounting location could be on a 5 to 25 degree angle in front of the axle connected to a bracket on the swing arm or vertically at the end of the swing arm. In any case custom mounts may need to be fabricated on the axle/suspension and trailer frame.

It is important to remember that shock absorbers should not be used to modify spring rate to increase the carrying capacity of the trailer unless they are specifically designed to do so such as rubber springs and some air bag systems.

Hopefully, this has given you some insight into ways shock absorption technology can be used on your trailer. Always remember to evaluate the type of trailer suspension you have and the ride quality or handling issues you are experiencing before making a decision. Contact us with your shock absorption and Trailer Tech questions, we’re happy to help! Thanks for reading!

Trailer Tech: Importance of Wheel Balancing

Welcome back to Trailer Tech

Today, we’re taking a look at the importance of wheel balancing, the different types of balancing and how this applies to your trailer. It is sometimes thought that there is no need to balance your trailer’s tires, but we’ll show you why it’s a good idea to do so.

Wheel balancing is a critical aspect of any vehicle’s correct operation at speed, as doing so will reduce tire wear and component wear caused by vibrations in the running gear. In extreme cases, tires can bounce down the road due to excessive vibration. It is important to note that not all trailer’s wheels come balanced from the factory or dealership.

Wheel balancing generally comes in 2 forms. "Off-vehicle" wheel balancing is the most fundamental in that the rim and tire are removed and mounted on a balancing machine, then reinstalled on the vehicle. Off-vehicle balancing is certainly more common and a necessity in any tire shop as an unbalanced tire greatly reduces tire life. This method does not balance the axle and hub assembly to the rim and tire assembly and is thus more suited to short distance and low or moderate speed as well as off road usage.

The minimum requirement in wheel balancing

Balancing the tire to the rim as well as the rim to the hub assembly requires "on-vehicle" balancing, generally performed after, and in addition to the off-vehicle wheel balancing described above. Even though on-vehicle balancing often requires a shop with special equipment and training; it can help reduce running gear vibrations coming from inboard sources with most noticeable gains visible in long distance and highway driving as well as in longer axle and hub assembly life.

Balancing heavy hub assemblies to the rim and tire can improve ride quality

Please contact us with your Trailer Tech questions, we're happy to help. Thanks for reading!