Timbren Suspension Enhancement System - GMC Sierra, 2004
Timbren's Suspension Enhancement System has hollow rubber springs that absorb the brunt of the force on both the front and rear of the GMC Sierra, helping to reduce sag and sway ensuring better handling, better traction and a smoother ride.
Features:
- Improves suspension and handling
- Prevents body roll with improved weight distribution
- Stabilizes the front or rear of the GMC Sierra for better handling of heavy loads
- Adjusts progressively to the road and the load so you always have a smooth, comfortable ride
- Provides additional support as needed
- Allows the spring ample movement while at the same time providing cushioning for light loads
- Increases stability and great performance while cornering, swerving or hauling large loads
- Takes the brunt of bumps and rough roads
- Extends the life of your GMC Sierra's suspension
- Designed to work with a suspension system that is in good working order
- Requires no air hoses, compressors or manual adjustments
Specs:
- Includes 2 Aeon hollow rubber springs, GMC Sierra-specific brackets and hardware for simple installation
- Replaces axle bump stops on frame
- No drilling required
- Capacity: 14,000 lbs
- Do not exceed the GMC Sierra's weight-carrying capacity
- Designed to work with a suspension system that is in good working order
- Limited lifetime warranty - satisfaction guarantee

The resistance from Timbren's Suspension Enhancement System works with the GMC Sierra's factory suspension to keep the GMC Sierra level, thereby improving your driving performance. When a truck bed is loaded, the rear of the GMC Sierra will sag under the load, and the front will sag under the burden of heavy equipment such as a snow plow. In this case, the axle is handling not only the weight of the load, but more of the GMC Sierra's weight as well. Because less weight is on the opposite axle, those tires are making significantly less contact with the road meaning there is less traction and therefore a decrease in overall control, handling and stopping.

The Timbren system has a GMC Sierra-specific bracket that will be bolted onto each frame rail above the front axle. Hollow rubber springs are bolted to the bottom of the bracket, hanging down so that the bottom of the spring is touches the axle. Because the spring is already making contact, it is working at once to cushion and support the GMC Sierra's existing suspension.

Timbren Suspension Enhancement Systems are designed to work progressively. When the hollow rubber springs are compressed, the convoluted design causes them to quickly collapse along the folds. Once the folds are compacted, the stacked barrel shape provides increased resistance, stiffening the suspension and keeping the GMC Sierra level.

Each hollow rubber spring works independently to support the driver's or passenger's side of the GMC Sierra. This is helpful when you swerve or make sharp turns. Each spring is activated when it is needed, so body roll is greatly reduced. The independent action also works well when hauling off-center loads.

Timbren's Suspension Enhancement System will raise the front of the end of the GMC Sierra when heavy equipment, such as a plow, is attached. Headlight beams will be pointed in the right direction and tire wear will be reduced. If the plow is off center or has an extension, the hollow rubber springs will automatically compensate for this as well.

Another great feature of the rubber construction is that the springs absorb most of the road shock, creating a smoother, more stable ride overall. Wear and tear on the factory suspension is also lessened as the rubber springs work to prevent bottoming out on rough roads.
Compared to the competition:
Timbren's suspension enhancement systems are much easier to install than air springs - no air hoses are needed to be run, no compressors or gauges to hook up, and no manual adjustments necessary. The rubber construction causes Timbren's springs to be more elastic than similar products constructed of micro-cellular urethane. More elasticity allows for a more comfortable ride because the rubber has more travel.
GMFK25S - Front or Rear Suspension Enhancement System with Aeon Hollow Rubber Springs by Timbren
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GMC Sierra Accessories