Why does my 5th wheel shake? (5+ reasons)

In this blog post, we will answer the following question: Why does my 5th wheel shake? We will discuss possible reasons why your 5th wheel shake and how to fix the issue.

Why does my 5th wheel shake?

There are several possibilities why your 5th wheel may shake, let’s analyze them:

  1. If your fifth wheel shakes while driving, it is due to the running gear (tires, wheels, shock absorbers and axles). In this case, the best course of action is to check the entire system. 

The problem can either come from a bad alignment or significant soiling of the wheels, an imbalance, advanced or irregular wear of the tires (by a lack of parallelism), a lack of tire pressure, or simply a significant drought which affects their capacity to absorb the roughness of the road. You should be aware that the slightest defect in balance can cause vibrations.

  1. If you recently had the stabilizer bar silent blocs replaced, there may be some play that is causing vibrations. Ditto for the ball joints of this same bar. If this happens, you must get to an auto workshop as soon as possible, or lose one of your wheels coming off while driving. No need to tell you how dangerous it can be.
  1. If you feel your fifth wheel is shaking during acceleration, the problem is with the engine. For example, there may be a problem with the spark plugs that causes one of the cylinders to fail, causing vibrations and forcing your engine to work with only 3 of its 4 cylinders. 

But it can also come from other problems, such as engine misfires, clogged filters, faulty constant velocity joints or simply the use of poor quality fuel.

  1. If your fifth wheel shakes during the gear change, it is the transmission or the running gear that may be involved. However, you can exclude this last possibility if you have recently passed the technical control. Indeed, motorhome workshops pay special attention to their proper functioning. 

If the vibrations go away when you are in neutral, you can be sure the transmission is responsible.

  1. If your fifth wheel shakes during braking, the problem is sure with the braking system. Indeed, if the surface of the rotor is worn unevenly, the adhesion of the brake pad and the calliper is no longer ensured correctly, thus causing vibrations.
  1. If your 5th wheel shakes while parked, it may mean that you didn’t stabilize and level it properly. Instead of a drawbar at the front, fifth wheels have two dropouts at the front. A first adjustment can be done manually with the pin, then the leveling will be done by the electric motor whose switch is located at the front, on the left under the nose of the fifth wheel trailer.

The principle of stabilizing a fifth wheel trailer is very similar to that of a trailer. Instead of a drawbar at the front, fifth wheels have two dropouts at the front. A first adjustment can be done manually with the pin, then the leveling will be done by the electric motor whose switch is located at the front, on the left under the nose of the fifth wheel. 

Some fifth-wheel trailers have a light for easy installation in the evening, the switch will be near the leg switch.

Then there will be stabilizers in the two rear corners, their deployment is done manually with the crank or a drill with socket, or with the switch located on the left in front of the fifth wheel.

How to use the stabilizers and level the 5th wheel trailer

First of all, there are several systems for stabilizing a trailer and leveling it; manual stabilization systems, electric stabilization systems, automatic electric stabilization systems and automatic hydraulic stabilization systems. 

It is important to know that stabilization systems that are not automatic, are not designed to lift and level the RV, but to prevent vibrations and swaying when someone is moving around in the RV. It is also important not to deploy the stabilizers to their maximum, if the slope is too steep, blocks should be used under the stabilizers where the ground is lowest.

If you have a problem with your stabilizers or stabilization system, see the article on the subject in our troubleshooting guide.

Manual or electric stabilization systems for a fifth-wheel trailer

You must first be level across the width by placing the trailer in an already levelled area or by using an accessory such as blocks under the wheels.

To make sure you’re level, you can use a standard level and affix it across the width of the RV and then down the length. It is also possible to attach two small levels directly to the RV, usually on the front left corner, one on the sidewall and one on the front wall. 

For the tech-savvy, there is now a small device that can be attached to the panel inside the front trunk. The device will provide the RV level across width and length directly in an app that can be downloaded to your smartphone.

Electric and hydraulic automatic stabilization systems for a fifth-wheel trailer

Electric or hydraulic automatic stabilization systems do the work for you. Just stand in a fairly level location, the RV should be level across the width and press the system button which is usually located on the left side of the front storage compartment, or near the control panel. control inside for motorized vehicles. 

This system will lift and adjust the RV to be level. There is obviously a limit as to the height difference that these systems can compensate for.

What if the manual stabilizer is difficult to deploy?

  • Check the stabilizer worm screw, it may need lubrication.
  • Check that the gap between the ground and the RV is not too large, blocks may be required if the stabilizer does not extend enough.
  • Make sure not to lift the weight of the trailer with the stabilizers. If the trailer is not level, it must be adjusted with blocks under the wheels or with the jack or front legs.

What to do if the trailer’s electric actuator does not work?

  • Check that there is a 12V current.
  • Check that the cylinder is properly connected.
  • Check the fuse located in the cylinder.

If the cylinder is not operational, you can operate it manually by inserting the crank into the hole covered by the rubber plug on the top or side of the cylinder.

What to do if the electric front legs of the fifth wheel do not work?

  • Check that there is a 12V current.
  • Check that the stabilizer is properly connected.
  • Check the fuse located on the wire near the stabilizer motor.

If the legs do not work, they will have to be operated manually.

  • Take the crank provided for this purpose supplied with your fifth-wheel trailer.
  • Find access to the paws. Usually through a front storage compartment where one of the propane tanks is located or through a small hole accessible directly on the wall in front of one of the legs.
  • Insert the crank and turn clockwise or counterclockwise to retract or stretch them.

What to do if the automatic stabilization system does not work?

  • Check that there is a 12V current.
  • Check that the panel and the stabilizers are properly connected.

What to do if the steering wheel of my 5th wheel is shaking?

If the vibrations appear around 55 mph, it means that the problem is with the front tires, and at around 70 mph, it is on the side of the rear tires that you have to concentrate.

The most common causes involve transmission. To find out, you must see if you feel a delay in the response of the transmission to your commands if they are not correctly transmitted to the wheels, or even worse, if precisely the vibrations are more important during manoeuvres. 

If this is indeed the case, take a few minutes to inspect the underbody for any leaks (transmission fluid, for example). If the search proves successful, you can make an appointment immediately with your mechanic.

How to prevent my 5th wheel from shaking?

Make sure to respect the technical inspection deadlines. Indeed, during these, the tires, the condition of the suspension and the steering are checked, which allows you to drive more quietly.

You can also consider the devastating effects of taking sidewalks a little too wild. This unnecessarily tires the entire running gear and easily creates imbalances in the rims and therefore vibrations.

Conclusions

Although seemingly harmless, vibrations in the 5th wheel trailer can be a symptom of a more serious problem, such as a stalled wheel. It is important for your safety on the road to take this problem seriously, take the time to diagnose it, and go to an auto shop for any necessary repairs after it is done.

Please feel free to share your thoughts and opinions on possible reasons why a 5th wheel trailer may shake. 

FAQ on Why does my 5th wheel shake?

Should my 5th wheel trailer be level when towing?

Yes, your trailer should be level when towing to improve your driving stability, braking performance, ground clearance,  and ultimately to prevent unwanted movement. 

What happens if your trailer is not level?

If your trailer is not level when towing, it will affect your braking performance, handling and it will cause your trailer to wear out more quickly. Another danger when your trailer is not level is that it can sway, causing unnecessary accidents. 

How do I stop my trailer from swaying when towing?

To stop your trailer from swaying when towing you’ll have to use anti-sway bars and shock absorbers. The transfer of load between wheels on the same axle can affect the balance of the vehicle. !

What do sway bars do?

An anti-sway bar is a U-shaped steel tube that interconnects the wheels of an axle. The stabilizer bar compensates for sway because as the suspension on one side compresses, it forces the suspension on the opposite side to compress as well.

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