The last thing you want is for your mobile home away from home to suddenly no longer be… mobile. Whether you’re at home or on vacation, having chassis issues is going to keep you grounded. So, here’s what you need to know about motorhome chassis repair, how to fix the problem, and most importantly, how to stop it from happening again.
What’s a Motorhome Chassis?
The chassis is the whole foundation of your motorhome. It underpins the entire structure above, enabling the vehicle to enhance on-road performance and driver handling.
This base-frame, generally constructed out of pressed-steel, forms a ‘skeleton’ that attaches all the vehicle’s vital elements together.
Components such as the axle assemblies, transmission, engine, steering mechanism, wheels, suspension components, and fuel tank, are all secured to this frame.
So if this malfunctions, you are in a no go zone…
What’s Gross Vehicle Weight?
The Gross Vehicle Weight is the maximum weight your chassis can safely bear without causing defects or malfunctions.
The GVW advertised on your RV includes the chassis, body, engine, gas, oil, interior furnishings, cargo, yourself, and any passengers you are traveling with. The GVW is not affected by additional trailer weight.
You mustn’t exceed the GVW of your vehicle to ensure maximum protection and minimal maintenance to your RV – in some jurisdictions exceeding your GVW may violate various laws as well.
RV Chassis Leaning: Causes and Prevention
So your motorhome seems to be leaning to one side? There are varying causes, however, most causes are repairable. Here’s a list of reasons your chassis could be leaning.
Spring Sagging or Imbalance
One of the most common reasons for leaning is that the front and/or rear springs of your vehicle are sagging. This is a relatively common issue caused by the natural deterioration of the spring rate in leaf or coil springs.
As the vehicle is used, even sitting, there is always a load on the springs. Over time this load weakens the springs to a point where they can’t hold the vehicle up the same way anymore and will eventually completely fail and break into two or more pieces. Overloading the weight capacity of your springs can also cause them to weaken or break prematurely. Some people will go as far as taking the weight off of the chassis springs and placing the unit on stands while sitting for long periods of time.
So is it a simple fix? The answer is that it usually can be! You’ll need to have your springs wholly replaced. This, unfortunately, isn’t cheap but it is the only solution to your issue. It’s often wise to replace the spring on the other side of the axle as well as the other spring will likely have some kind of deterioration as well and failing to replace it will cause irregular weight distribution and lead to premature failure of one or more of the springs again.
Mechanics who suggest only replacing one side are likely trying to make a quick sale and not looking out for your best interest. While you can get away with only replacing one side, this should be your decision and made by weighing out your cost/risk with your mechanic to ensure that you are making the right choice for your future.
Irregular Weight Distribution
Another cause of vehicle lean could be improper weight distribution on your chassis.
As mentioned before, the GVM of your vehicle is a vital piece of information when it comes to weight distribution. Unfortunately, depending on the setup of your particular RV it can be easy to overload a particular spring when you’re loading up your gear to head out. When a particular spring is overloaded as mentioned previously it will cause the spring to wear out prematurely. It might also cause the unit to lean. Often times it’s just a matter of distributing the weight in the unit evenly.
Using slides without the use of a support mechanism often in the form of leveling jacks will often cause a lean as well. This is taking the weight of the slide and distributing it, even more, off-center and causing an uneven distribution of weight on the unit. Many units have built-in leveling systems, however, even if the unit does not have a built-in system, having a way to level and support your RV while stationary aside from the chassis suspension is vital.
Improper RV Loading
Despite multiple checks carried out on the manufacturer’s chassis, no amount of calculating will make up for the amount of stuff you’ll add to your vehicle once you have it home.
Food, homeware, luggage, and furnishings will all contribute to the GVM. If this isn’t loaded correctly, then it can cause an imbalance or overweight situation.
Distribute the additional weight evenly so that the chassis stays level and within your GVW. This will prevent you from any complications further down the road.
Some RV’s forgo the use of steel leaf or coil springs and use air-ride suspensions instead. Air ride suspensions consist of a few basic components including; an air system to supply compressed air, airbags in place of steel springs, and leveling valves to control the height of the vehicle.
There are many configurations manufacturers use for leveling valves including; one valve for multiple axles, one valve per axle, two valves where one controls the left side airbags and the other controls the right side airbags.
In the last example, if a leveling valve fails it can either over-inflate or under-inflate a particular side causing a lean in the vehicle. In this case, the repair is often simple and straightforward.
Depending on your particular air-ride system the air suspension can make up for improper weight distribution by compensating the amount of pressure in the side that has the heavier load through the use of the leveling valve. You still can, however, exceed the vehicle’s GVW with an air-ride suspension.
Air leaks in the system can also cause the pressure in the bags to dissipate to the atmosphere and lean or drop the suspension altogether.
Proper inspection and maintenance will go along way in ensuring the longevity of your system and is the best way to prevent downtime.
Occasionally and rarely vehicle frames can run into issues – some of these issues include; bent frame members, loose frame members, cracked or broken frame members, and rust jacked fame members.
Every frame member (Frame rails, cross members, fasteners) is integral to the vehicle and was designed and engineered in a very specific way. When these components fail they can cause issues from weakened structural areas, excess frame flex, poor handling, misalignment, all of which could make for unsafe driving conditions.
Oftentimes these failures are repairable, however, some of the repairs can be very extensive and as a result expensive and time-consuming. These failures or deteriorating conditions are sometimes not noticeable while driving but can lead to a major failure. One of the best ways to catch these failures is regular inspection of your unit, often when the unit is having an oil change as an example.
quite often some of the more major failures that happen with frames, while repairable, are often not cost-effective. This lends even more to the idea of regular inspection and preventative maintenance.
Signs Your Chassis Needs Repair
Now, let’s take a look at some of the most typical red flags that indicate your chassis needs repair:
Increased Fuel Consumption
Keeping track of your fuel consumption could indicate an issue with multiple chassis items including sagging, poor alignment (sometimes caused by sagging springs), or worn out suspension components.
If you notice a change in your vehicle’s performance or fuel economy it’s best to have a qualified technician take a look to get the problem solved and help eliminate any potential bigger problems down the road.
Is your RV suddenly starts creaking, banging, rattling, squealing, do these unexpected noises fill you with dread? Many factors could be causing these sounds, from dust build-up in brakes to major failures in driveline components.
Clunking, banging, or squealing sounds are also the result of an abnormal condition with a chassis component and should be inspected immediately.
Delaying repair on chassis components could increase the chance of a major failure which, in turn, could result in irreversible damage or conditions where an accident would be unavoidable.
If your RV is pre-loved, it may have been subjected to impaired driving. Uneven weight distribution, handling, and historic incidents may have had an impact on the chassis.
This should’ve been identified before your purchase. However, if you are having issues with steering, best get it checked out.
Weak or broken springs or axle tracing devices (torque rods etc), and/or worn out steering components is an extreme safety concern. The worse it gets the more dangerous it is to drive.
As mentioned above, unresponsive or over-responsive steering can indicate compromised chassis components. The steering mechanics are attached to the chassis. Any maneuver you make will result in the chassis’s same movement.
If you have steering issues, it could indicate that the chassis or steering mechanism components have started to fail or require adjustment.
The Rapid Wearing Out of Tires
Finally, if you notice your tires aren’t lasting as long as they should. You are continually having to replace them (which on an RV can be expensive!). You should probably get the chassis checked out.
The chassis is designed to increase road performance and reduce issues to ensure that your vehicle travels smoothly and without resistance.
If the wheels are out of alignment, it can cause the tires’ deterioration and/or uneven or abnormal wear on your tires. Your wheels must be realigned to prevent further damage.
Are You Ready to Handle Your Motorhome Chassis Repair?
Motorhome chassis repair may seem to be an ‘out of sight, out of mind’ matter, but you can see what damages faulty chassis can cause to your vehicle and your finances.
So, book an inspection today to help us get you and your home safely back on the road!