What is a Leaf Spring? Can Timbren SES do everything a Leaf Spring can?

Are the old ways always better? Well, when it comes to suspension technology, that’s not true. Today we’re gonna take a look at Hellwig leaf spring helpers and compare them to Timbren SES. Hopefully, this short article will help you to see that Timbren SES is superior to Hellwig.

What is a leaf spring?

Hellwig leaf springs are helper springs designed to sit on top of the existing leaf springs at the rear of your truck. They work in conjunction with the factory spring pack to increase the spring rate of the truck. Hellwig offers several types of leaf helpers with different load capacities and applications.

Hellwig leaf springs support systems can add an additional load capacity ranging anywhere from 500 lbs up to 3500 lbs. These helper springs increase the suspension’s spring rate but do not increase the GVWR.

The price of a leaf spring kit ranges anywhere from $100.00 - $1000.00.

The following is taken from a Hellwig EZ-990 instruction sheet:

1. Place the spring on top of the mainspring with the long end toward the rear of the vehicle.
   
   
2. Slide the spring back and forth so the hump doesn’t touch the factory vehicle U-bolts but to maximize the distance between the leaf tips and the underside of the vehicle.
   
   
3. Place the U-bolts with the short legs on either side of the hump as shown in the diagram. Using the included cross bars, washers, and nuts, tighten to the recommended torque.
   
   
4. Use the longer legged U-bolts on the outside cups of the spring as shown in the diagram. Attach them once again using the crossbars, washer, and nuts. It may be necessary to either jack the vehicle up by the frame allowing the suspension to droop or use a C-clamp to compress the spring to start the nuts.
   
   
5. Adjust the crossbars on the end of the springs so that the adjacent leaf tip will not contact the crossbar when the spring is deflected. It may be necessary to move the spring stack fore or aft for best alignment.
   
   
6. Adjust the U-bolts at the spring end to desired preload. The minimum tension adjustment is having enough tension on the end U-bolts so that they do not loosen or rattle and move when the vehicle is driven over rough or bumpy surfaces. Maximum adjustment is when the leaf cups are 1/4” from the main spring.
   
   
7. When adjustment is complete, double-nut to lock in adjustment.
   
   
8. Lower the vehicle to the ground and check your installation for clearance on all undercarriage components, wires, fuel, brake, and air conditioning lines.

With the right tools, a first-time installer could take up to 2 hours.

What is a Timbren SES?

Timbren SES suspension upgrades are made of natural rubber designed to replace the existing bump stops. Depending on where the bump stops are located, SES rubber springs typically fasten to the frame, the axle, or the truck’s leaf spring suspension.

Designed as a helper spring to assist with heavy loads, Timbren SES upgrades do not replace or override the existing suspension. Most SES kits for pickups are rated for 6000 lbs additional capacity while others add up to an additional 12,000 lbs.

The average SES kit for a half ton pickup lists for about $300.00.

The following outlines five simple steps to install an SES kit for a 2023 Chevy Silverado:

• Raise vehicle
• Remove OEM bump stops
• Assemble Steel disc, rubber spacer and Aeon rubber spring (as shown in diagram). 
• Mount to vehicle frame using Timbren supplied fasteners.
• Lower vehicle

This easy installation takes less than 30 minutes.

Leaf springs or Timbren SES: Which is better?

Our comparison will be restricted to the following two products:

Timbren SES part # GMRS15 and Hellwig EZ-990 Helper Spring Kit.

SIMILARITIES:

Both Timbren SES and Hellwig EZ-990 helper springs...

• Provide additional lift
• Prevent sagging and squatting
• Stabilize the load
• Require very little maintenance

DIFFERENCES:

1. The first (and obvious) difference between the 2 products is the material: The Hellwig EZ-990 helper springs are made of tempered steel; Timbren SES upgrades are made of natural rubber.
   
   
2. The second (and not-so-obvious) difference between the 2 products is their spring rate: Hellwig metal springs have a linear spring rate i.e. the metal springs deflect at the same rate all the way to full deflection. On the other hand, SES hollow rubber springs have a progressive spring rate, i.e. the spring rate increases as they deflect down to full deflection.
   
   
3. The maximum additional load capacity of the Hellwig EZ-990 = 2,000 lbs. designed for lighter assistance. On the other hand, SES upgrades provide up to 12,000 lbs. designed for heavier assistance.
   
   

Which product gives you the biggest bang for your buck?

In order to understand why Timbren SES are superior to Hellwig leaf springs, you need to understand two innate characteristics of an Aeon® hollow rubber spring - used in every Timbren SES product:

• Progressive spring rate
  Unlike metal springs that have a linear spring rate, Aeon® rubber springs have a progressive spring rate, a rate that increases as more weight is added to the truck.
  
  
• Hysteresis (self-damping)
  Unlike metal springs that need shocks to absorb the energy created when they compress, Aeon® rubber springs are self-damping, able to absorb the kinetic energy by themselves.

These two characteristics offer some unique advantages: