TrestleJacks FAQ

General Questions:

What is a TrestleJack?

Whenever you need to change a tyre or repair brake linings or bearings on a heavy load trailer, you can rely on the TrestleJack 30-Ton R22.5 Workshop unit to cut downtime dramatically. It lifts a trailer axle faster than any conventional system - in fact, the entire process can be achieved in less than 10 seconds.

The TrestleJack uses driving motion from the tractor to lift and lower trailer axles. Because nobody is allowed close to or underneath the trailer for the lifting and lowering procedures, the result is a far safer working environment. Once the TrestleJack is upright, it transforms into an axle support stand with a safe working load of 30 tons. Where a complete axle or empty trailer needs to be lifted, you will need to use two TrestleJacks per axle.

Which trailers are supported by TrestleJacks?

TrestleJacks are designed to work on most commercial trailers fitted with standard R22.5 tyres.

Tyre sizes tested include:

- 11R22.5
- 12R22.5
- 315/70R22.5
- 315/80R22.5
- 385/65R22.5
- 425/65R22.5

Taut-liners, Tipper Links, Flat beds, Refrigerated Trailers and Tankers have been tested with TrestleJacks 30 Ton R22.5 Workshop units.

Does TrestleJacks work with trailers fitted with Round or Square Axles?

Both axle types are supported. 

How safe is it to use TrestleJacks?

Before using TrestleJacks it is the operator’s responsibility to ensure that they are familiar with the content found inside the standard operating procedure and that it is understood and followed appropriately.

TrestleJacks is the safest lifting and standing device currently available on the market. During the lifting and lowering process no person is allowed close to or underneath the trailer. The driver is kept safe in the cab during the process.

In the upright position, the TrestleJack is a safe axle standing, supporting or blocking device. The cup’s position of five degrees over the top dead center ensures that no rolling forward can occur without applying significant force. In the event where a tyre needs to be changed on a sloped surface, a chock block can also be placed in front of the TrestleJack and the belt can be used to securely lock the TrestleJack into the upright position.

TrestleJacks are load tested with a safe working load of 30 Tons. A load certificate valid for 1-year, a risk assessment and standard operating procedure is also made available to help users familiarize themselves with the use of the product. Hands-on training and online training videos are also provided to TrestleJacks clients. Trainees attending the hands-on workshop are supplied with a certificate of attendance.

South African Bureau of Standards (SABS) currently does not have an official standard available and we are in the process of establishing a standard in conjunction with the organization.

Can I use TrestleJacks in a roadside breakdown?

Yes. TrestleJacks have been tested in mud, on a dirt road, paving & tar roads. Both empty and loaded trailers have been tested. As with any lifting or standing device an even and hard surface needs to be identified to lift and support axles. Please ensure that the operator is familiar with the content in the standard operating procedure available on the website. Also see the video where we lifted an axle of a loaded trailer after removing the wheels.

Will the TrestleJacks slip when I drive onto it?

TrestleJacks have been designed to work on most surfaces. Placing the TrestleJack close to the spring blades or air bag mounting point ensures that no slipping could occur. When driving onto the product and in the event where the TrestleJack does not grip to complete the lift, a belt component is supplied with the product and it is recommended that it is used to secure the TrestleJack against the axle to prevent any movement. The belt hooks onto a d-shackle found on the rear gusset. Once the belt is secured to the rear wheel of the tractor, the belt will hold the TrestleJack securely in place. The trailer axle will continue to be lifted provided the vehicle continues to move slowly in its original direction. The TrestleJack continues to move into the up-right position holding the axle securely in place. Please see the standard operating procedure available on how to use the belt. 

How much does a TrestleJack Weigh?


Do I need to use two TrestleJacks per axle?

Only when lifting entire axle will two TrestleJacks be required. In the event where an entire trailer needs to be lifted, please ensure that the trailer is without a load.

Can I lift two or more sides of a trailer when rotating tyres?

Yes. TrestleJacks can be placed on the same side or opposite sides and lifted at the same time to be able to rotate tyres. When lifting an entire axle, two TrestleJacks will be required.

Can the TrestleJack damage the trailer’s axles or slag adjusters?

TrestleJacks are constructed with mild steel. Trailer axles are built with a harder steel. The result is that the TrestleJack cup will wear away rather than causing any damage on the trailer axle. The TrestleJack's design prevents any contact with the slag adjusters found on trailers. On most trailers it is best to place the TrestleJack in the loading position on the side of the axle where there is no slag adjuster.

Will TrestleJacks work on trailers fitted with airbag suspension?

Yes. In all our tests with trailers fitted with airbags, TrestleJacks did not get in the way or came close to them. No damage was made. 

Hydraulic Jacks are cheaper than TrestleJacks?

Would you allow someone to use a shifting spanner when doing repairs on your truck? If yes, then you may find specialised tools not appealing. If no, then please read further:

Hydraulic Jack Overview:

Since 1855, before the heavy commercial trucking industry as we know it started, people mainly used the hydraulic jack for lifting vehicle axles. The hydraulic jack is a product that was designed for a general purpose and normally supplied with the tractor. The tractor supplier is not aware of the type of trailer that will be used and tractors are also not limited to specific trailer types. Up until now there never existed a lifting device for trailers. Further to being a generic device a hydraulic jack was not designed for local operational conditions.

Hydraulic Jack Safety:

As per the user guide of a hydraulic jack, it clearly states that the device is made for lifting a load and not holding it. It specifically states that an axle support stand must be used before any work can be started. Many operators ignore this fact and are introducing unnecessary risks that could lead to injuries. Occupational health and safety regulations specify that all precautions should be taken to ensure personnel safety.

Like a shifting spanner, a hydraulic jack has adjustable components. On a hydraulic jack, a visual inspection cannot detect potential failure. When a hydraulic jack is left to lie on its side, a seal may become dry which may lead to cracks and ultimately failure. The real danger comes in when lifting an axle of a troubled wheel, taking it off and letting it stand on the hydraulic jack. If the seal of the hydraulic jack is leaking, a slow decent will take place and when trying to replace the wheel, an operator will notice that the axle is too low. The operator is required to crawl underneath the trailer and again pump the hydraulic jack to create lift. In this event a risk is introduced by means that the hydraulic jack could slip and shoot out injuring the operator or worst a load collapsing onto a person.

Further to potential seal failure, the head on a hydraulic jack does not grip a round axle properly. With a 5mm wide grip on a round axle, slipping off a hydraulic jack could spell disaster.

Most HCVs leave on a long haul without the most needed emergency tool for tyre repairs, a reliable lifting device.

Hydraulic jacks, being a generic tool, are not made to lift trailer axles effectively. Trailer axles are almost 100mm higher which means that additional supporting equipment - like a sleeper block - is required to be able to provide the required reach. Even then, lifting a trailer axle is still not straight forward, nor easy or safe.

Hydraulic Jack Cost to Transporter:

For any transport operator, time literally means money. In one of our recent studies we have found that we can save operators a minimum of 25 minutes during a breakdown or a service when lifting one side of an axle. When having to lift more than one side or more than one axle at a time, the time saving escalates dramatically, translating into huge costs savings. For further details of the study please see our workshop section available on this site.

There are many reasons to consider TrestleJacks, but the most important fact is that TrestleJacks is an axle stand with lifting capabilities that far exceeds that of conventional systems.

Transport Operator Specific:

How will the driver know that the upright standing position has been reached?

The TrestleJack's design ensures that when the highest lifting point is reached the TrestleJack creates a positive stop that provides direct feedback to the driver in the cab. It may happen that the driver drive too far and the TrestleJack’s baseplate is not level to the surface. Releasing the brakes will cause the TrestleJack to correct it’s position and level the baseplate to the surface. Another way of measuring how far a driver needs to go is to place a chock block about 400mm from the rear tyre of the tractor. This will also provide additional feedback to the driver.

What happens if the driver drives over the TrestleJack when lifting an axle?

In our experience during field tests, most trailers fitted with 11R22.5, 12R22.5, 315/70R22.5 and 315/80R22.5 it is safe to drive over the TrestleJack. Driver training is important and we have found that once a driver has done the operation for the third time, confidence and know-how helps the driver realize when to stop and position the TrestleJack correctly. A chock block can also be placed 400mm behind the tractor’s wheel to ensure that the driver stops when the upright position has been reached. TrestleJacks design also notifies the driver in the cab through a positive feedback that the TrestleJack is in the upright position.

Where do I store a TrestleJack when buying one for each vehicle?

TrestleJacks can be stored in the trailer or tractor’s toolbox. The TrestleJack can also be secured on top of one of the spare wheels. We are currently working with trailer manufacturers to design a bracket than can be mounted onto the trailer for easy and secure access and storage. 

What if someone steals or illegally sells the TrestleJack?

TrestleJacks, unlike conventional lifting equipment (CLE), is a specialized tool. Normally CLEs are sold to willing buyers that have a wider use for the product. Sometimes CLEs are sold to individuals that use the CLE to steal tyres while drivers are sleeping. With TrestleJacks the driver has to be awake and drive the tractor to lift an axle and that event can be tracked via satellite. The only reason to sell a TrestleJack will be for scrap metal for a nominal fee. Implementing better controls and incentives for drivers can restrict the illegal selling of TrestleJacks.

Tyre Service Agent or Workshop Specific:

Can I unhook the trailer from the tractor to repair break linings and bearings?

Yes. Lifting the entire empty trailer by placing two TrestleJacks per axle can be done in 83% less time than current conventional ways. Before unhooking the trailer, the trailer stands once lowered, can be used as an anchoring point for the belt component which will create a locking mechanism to ensure no further movement is possible. Additionally chock blocks can be placed in front of the TrestleJacks for further stability. 

The real benefits of using TrestleJacks can only become a reality when combining effective and efficient business processes & procedures orchestrated by management, adopted by employees working with the tool. That means that when a client checks in a trailer that the lifting should be done immediately before unhooking the trailer from the tractor. For some organizations this may mean changing their current way of working, however the inconvenience of change will be minuscule compared to the effort and time saving achieved by using TrestleJacks.

Services and Warrantees:

Does the TrestleJack come with a warranty?

TrestleJacks comes with a limited 1-year warranty. 

It warrants this product against defects in workmanship for one year from the date of purchase. During this warranty period, this product will be repaired or replaced, at Trestle Jacks Pty Ltd discretion, without charge. Please read your instructions thoroughly and use this product only as directed. This warranty does not cover any damage due to accidental misuse, abuse or negligence. Repair or replacement as provided under this warranty is the exclusive remedy of the consumer. The seller shall not be liable for any incidental or consequential damage for breach of any expressed or implied warranty of merchantability or fitness for a particular purpose on this product is limited to the duration of the warranty.

What other services does Trestle Jacks Pty Ltd provide?

We place a high value on our client’s feedback and satisfaction. Based on feedback from the market we created the following services:

1) End user training

End user training is mandatory and is delivered on-site at the client’s premises. As a refresher or new starter course, on-line video based training will also be made available from our website to existing TrestleJacks clients. A certificate of attendance is issued to each trainee and products are automatically registered for warranty purposes once the training has been completed.

2) Load certificate renewal & product services

A TrestleJack load certificate is valid for only 1 year. We offer a certificate renewal service to all our clients at an additional fee of R750 per TrestleJack. Included is a product service whereby the rubber on the baseplate and stickers will be replaced (if necessary). The price does not include collection or delivery fees.