How to Install a Timbren SES Kit in 7 Easy Steps

Is your truck sagging under load?

This can interfere with its overall performance. In other words, if your vehicle doesn’t sit level, there are a number of problems you will encounter:

  • Proper front end steering alignment is thrown off balance, causing the vehicle to have delayed steering response. The ride will feel unsafe and out of control.
  • The braking distance is extended due to significantly less weight on the front tires. Braking distance is increased because the front of the vehicle is responsible for up to 70% of the vehicle’s stopping ability.
  • The position of the vehicle’s front end causes its headlights to point upward. This creates a nighttime road hazard by blinding oncoming traffic.
  • Due to the misalignment of the steering, tire wear is increased and there is potential for premature tire wear failure.
  • The misalignment causes an uneven tire footprint, which can decrease your fuel mileage. This is due to the uneven load and vehicle riding unleveled.

Here’s an easy solution that won’t take a lot of your time. Below is a quick guide and video that demonstrate how to properly install a bolt-on Timbren SES kit in 7 easy steps. The kit shown in the video is part number GMRCK15S.

*Before you get started, open the box and read the instruction sheet. Check to see how many components are part of the assembly, and make sure the kit is complete. If your kit is missing a component, be sure and contact customer service at

Step 1 Be sure to block your tires to ensure that the vehicle does not move during installation. Wheel blocks, also known as “chocks,” are often overlooked as a safety precaution. When positioned against the wheels, they prevent vehicles from rolling and causing potentially fatal accidents. Chocks should always be employed anytime your vehicle is resting on a jack or a slope, or if you are working underneath. Put the vehicle in park and apply the emergency brake. Then, wedge the angled chocks beneath the tires on both sides to keep the vehicle from moving.

Step 2 Use a jack to lift the vehicle and allow the axle to hang freely.

Put safety first! Make sure the transmission is in Park (or first gear if you have a manual gearbox) and that the parking brake is engaged. Switch the ignition off and remove the key. Check your owner’s manual for the locations of your vehicle’s jack points. There is typically one near each wheel. Warning: Do not put the jack under a body panel! Apart from the obvious damage to the vehicle, this incorrect procedure can injure or kill you. Also, don’t use the vehicle’s emergency jack. A hydraulic floor jack like the one in the video is sturdier, more durable, and better suited for this type of work. If your jack leaks fluid or shows other signs of disrepair, stop working and repair or replace your jack before you proceed.

The jack should make contact with a sturdy, unpainted area of the vehicle’s frame. If necessary, remove the tire to ensure you have adequate room to work.

Step 3 Unbolt and remove the OEM bump stop. Some OEM bump stops are held by friction inside the bump-stop cup. To remove this type, simply pry them out of the cup using a flat-head screwdriver. If they won’t pop out, they’re probably bolted to the frame like the one shown in the video. The bump stop is about 4” in length. In this case, you’ll need to use a ratchet with an extension.

Step 4 Drop the bolt into the hollow rubber spring. As you do so, be sure to feed the bolt through the internal washer (found inside the rubber spring) and up through the top of the spring. The internal washer is important because it prevents the bolt from pulling through the rubber spring as you tighten the assembly.

Step 5 Position the metal spacer over the top of the rubber spring, allowing the bolt to feed through the spacer. The rubber spring is too large and will not fit properly into the bump-stop cup. For that reason, the spacer helps to stabilize the rubber spring by giving it a flat surface on which to seat itself.

Step 6 Install Timbren SES assembly using existing holes in the frame. The Timbren-supplied bolt will thread into the existing hole in the frame located inside the cup. (Make sure the thread on the Timbren-supplied bolt matches the thread on the factory bump stop bolt.) Using a ratchet with an extension, work the Timbren-supplied bolt into the threaded hole up inside the cup.

Step 7 Tighten bolt and replace tire.  There is no specific torque value you need to match when installing a hollow rubber spring. The rubber spring needs to be tightened until it is snug, and no more. Once you’re done, repeat steps 1-7 on the opposite side of the vehicle.

Timbren SES kits are designed to keep your vehicle level at all times, loaded or unloaded. In fact, they’re guaranteed to keep your truck level and stable even under the heaviest loads.

Here are some of the benefits you will enjoy after you’ve installed an SES kit on to your rear suspension:

  • Increased Stability The progressive spring rate not only keeps the vehicle level – side to side and front to back.
  • Reduced roll and sway Less body roll and back-end sway means better handling when turning corners.
  • Cushioned road shocks The rubber springs smooth out rough roads, improving ride quality.
  • Easy installation With the proper tools, almost anyone can install a Timbren SES kit
  • Improved steering When the vehicle is level, the front tires maintain a better grip on the road.
  • Maintenance free Hollow rubber springs do not require any special ongoing care or upkeep.
  • Two best warranties Every Timbren SES kit comes with a Lifetime Warranty and a Customer Satisfaction Guarantee.

Check out this video to see what a Timbren SES installation looks like: