How overload springs affect your ride

What are overload springs?

Overload springs – sometimes called helper springs – are an additional set of leaf springs installed beneath the existing leaf springs. In fact, they’re designed to work with leaf-spring suspensions only.

The easiest way to understand how an overload leaf spring works is to think about it as a ‘muscle’ designed to help the vehicle when it’s weighed down while towing or hauling something heavy like a truck camper or a trailer.

Overload springs for a majority of trucks are already installed at the factory by the manufacturer. When your truck is weighed down with a heavy load, the rear begins to sag. As the rear suspension continues to sag, it forces the lower overload leaf spring to come into contact with the leaf springs above it.

If you don’t have overload springs on your half-ton truck, there are many helper springs available on the automotive aftermarket that provide many unique benefits. One such product is Timbren SES suspension upgrades.

What is the purpose of an overload spring?

How does an overload leaf-spring “muscle” work?

Factory overloads usually are situated between the leaf springs above and the axle below. Weighed down with a heavy load, the truck’s rear suspension begins to squat. As the rear continues to sag – sometimes several inches – the leaf springs eventually contact the overload springs. This causes the “muscle” to spring into action.

However, it takes a sizeable weight to force the leaf springs to drop low enough and contact the overloads in short order. In fact, quite often they don’t make full contact while the truck is towing or hauling. Unfortunately, this sort of suspension sag and squat can lead to some negative side effects which include:

• Side-to-side sway


• Body roll


• Poor handling


• Lack of control of the vehicle


• Increased stopping distance


• Misaligned steering


• Increased tire wear 

Fortunately, there are some alternatives available that can out-do factory overloads.

What are the advantages and benefits of helper springs?

Even though overload springs can help by reducing serious squat on the truck’s rear end, they aren’t very effective at mitigating side-to-side sway, body roll, and loss of control.

Fortunately, there are quite a few products on the market today that can remedy the problems mentioned above. There are helper springs that not only reduce sag and squat, they can also reduce roll and sway, poor handling, and misaligned steering.

First of all, let’s answer the question: “What Are Helper Springs?”

Helper springs are designed to assist your suspension springs. They do not replace them. Here is a list of some of the more popular spring helpers:

Steel helpers

Hellwig helper springs are supposed to sit on top of the leaf springs at the rear of your truck, working together with the existing suspension to keep the vehicle level under load. Hellwig helper springs are adjustable, easy to install and come complete with all the necessary hardware. They are designed to reduce sag and squat.

Super Springs is another option. Although similar to Hellwig, they take a little less time to install, offer a little more spring capacity and provide better unloaded ride quality. They are also designed to reduce sag and squat.

Coil assist

Coil Design Helper Springs mount to the U-bolts in the center of the leaf spring and attach to the frame above. They are designed to reduce sag and squat.

Airbag assist

Airbags were originally designed as an alternative suspension to leaf springs. Products like Air Lift and Ride Rite have been around for decades. Designed to sit between the frame and the leaf spring, they reduce sag and squat.

Sumo Springs are made from micro-cellular polyurethane. They come in different heights which allows the installer to fasten the springs to both the frame above and the leaf spring below.

Timbren SES Upgrades

Timbren SES upgrades are made from natural rubber, designed to replace the bump stops on trucks, vans and SUVs. SES upgrades do a lot more than just reduce sag and squat.

Which helper springs are best for you?

When trying to make an informed choice as to which helper springs are best for you, there are a number of factors that you should consider.

Design: Is the product simple or complex? Is it easy to install? Does it require a lot of maintenance?

Cost: Some products cost more than others. Which one will give you the biggest bang for your buck?

Ride quality: What is the ride like with and without a load? Does the product enhance the ride or compromise ride quality? Some helper springs don’t absorb road shock.

Stability: Just because the product levels the load doesn’t mean that the vehicle will remain stable. Some products don’t really address the problem of body roll and sway.

Longevity: How long has the product been on the market? Does the product have a good warranty? Does the company offer a customer satisfaction guarantee? Is a good warranty important to you?

Not every product – no matter how popular it might be – is designed to meet all your needs.

One particular product scores high markets because it checks off all five boxes. Timbren SES upgrades provide the following advantages:

• Simple design that provides easy installation


• Requires virtually no maintenance


• Affordable pricing


• Great ride quality


• Added stability


• No B.S. Lifetime Warranty


• 100-Day satisfaction guarantee

Are Timbren SES helper springs easy to install?

Let’s put it this way...

• Hellwig overloads take about 2-3 hours to install.


• Airbag assist can take up to 10 hours to install


• Timbren SES upgrades for a rear truck suspension usually take about 30 minutes to install.

Timbren SES upgrades are some of the simplest DIY projects you’re ever going to experience. They’re quick to install, easy to maintain, and warrantied for life.

For more information on Timbren SES helper springs click here.