Hellwig 985 EZ-990 Rear Helper Springs Chevy GMC 1500 88-98 Tundra 07-21

Vehicle Fitment

• 1988-1998 Chevrolet C1500 (2WD, All Trims, All Cab Styles, All Engines)
• 1988-1998 Chevrolet K1500 (4WD, All Trims, All Cab Styles, All Engines)
• 1988-1998 GMC C1500 (2WD, All Trims, All Cab Styles, All Engines)
• 1988-1998 GMC K1500 (4WD, All Trims, All Cab Styles, All Engines)
• 2007-2021 Toyota Tundra (All Trims, 2WD/4WD, All Cab Styles, All Engines)

Fitment Notes

• Chevrolet and GMC 1500: Fits the full GMT-400 half-ton pickup production run from 1988-1998, covering all cab styles (Regular Cab, Extended Cab) and box lengths across all trim levels. The C-designation is 2WD; the K-designation is 4WD.
• Toyota Tundra: Fits the 2nd-generation Tundra from 2007-2021 across all cab styles (Regular Cab, Double Cab, CrewMax), all bed lengths, all trim levels, and all available engines (4.0L V6, 4.6L V8, 5.7L V8) in 2WD and 4WD. Verify fitment for 2019-2021 model years as TruckSpring's fitment table was last updated through 2018.
• Does NOT fit the 2022+ 3rd-generation Toyota Tundra, which uses a completely different platform with a coil spring rear suspension.
• Mounts under the factory rear axle U-bolt plates - the existing factory U-bolts are replaced by the heavy-duty U-bolts included in this kit.
• Two spring assemblies are included - one per side of the rear axle.

Features

• EZ-990 medium-duty rear helper spring kit covering two distinct vehicle platforms - the GMT-400 Chevrolet/GMC half-ton pickups (1988-1998) and the 2nd-generation Toyota Tundra (2007-2021) - both rated at 2,000 lbs. of level load capacity.
• 2,000 lbs. level load carrying capacity - eliminates rear sag during towing and heavy hauling, restoring proper ride height and improving vehicle stability and handling under load.
• Mounts under factory rear axle U-bolt plates - standard EZ-990 installation that replaces the factory U-bolts with the heavy-duty adjustable U-bolts included in the kit.
• Factory ride completely unaffected when unloaded - the spring engages progressively as load is applied, leaving the factory empty-vehicle ride character unchanged.
• Reduces leaf spring wrap-up under load, improving rear-end stability, wheel hop resistance, and towing consistency.
• Fully adjustable via heavy-duty U-bolts - tune spring engagement and load response with simple hand tools.
• Adjustable independently per side - accommodate uneven side-to-side loads or asymmetrical cargo/tongue weight distribution.
• No drilling required - complete bolt-on installation.
• Hot-formed and heat-treated ASTM 5160 alloy spring steel for maximum strength, shape retention, and long-term resilience.
• Black powdercoated and plated components for corrosion resistance in all weather and work conditions.
• All mounting hardware included - install with common hand tools.
• ISO 9001:2015 certified manufacturing at Hellwig's Visalia, California facility. Made in the USA. Backed by a Lifetime Warranty (for the life of the vehicle).

Specifications

• Part Number: 985
• Series: EZ-990 Medium Duty Helper Spring
• Product Type: Rear Helper Spring Kit
• Level Load Capacity: 2,000 lbs.
• Spring Material: Heat-treated ASTM 5160 alloy spring steel
• Position: Rear axle
• Quantity: 2 spring assemblies (one per side) + 4 U-bolts
• Finish: Black Powdercoated and Plated
• Adjustable: Yes, via heavy-duty U-bolts (independent per side)
• Installation: Bolt-on under factory axle U-bolt plates; no drilling required
• UPC: 745662009854
• Warranty: Lifetime (life of the vehicle)

Included Components

• 2x EZ-990 helper spring leaf assemblies (one driver side, one passenger side, black powdercoated)
• 4x Heavy-duty adjustable U-bolts
• 1x Complete plated mounting hardware kit
• 1x Installation instruction sheet

Product Description

The Hellwig 985 EZ-990 Rear Helper Spring Kit is a medium-duty rear load assist kit covering two distinct platforms - the 1988-1998 Chevrolet and GMC C/K 1500 GMT-400 half-ton pickups, and the 2007-2021 Toyota Tundra - both sharing the same EZ-990 leaf geometry and mounting configuration. For the GM trucks, the 985 addresses the rear leaf sag common in the GMT-400 generation trucks that are routinely pressed into service decades after their manufacture, carrying loads that have exceeded their factory spring capacity through years of cumulative fatigue. For the Tundra, it solves the rear sag that 2nd-generation owners experience when towing trailers or carrying heavy bed loads close to the Tundra's payload limit.

Both applications use the standard EZ-990 installation method: the helper springs bolt onto the top of the factory rear leaf packs under the axle U-bolt plates, with the factory U-bolts replaced by the heavy-duty adjustable U-bolts included in the kit. These U-bolts serve as both the mounting method and the rate adjustment mechanism - tighten for increased engagement and load resistance, loosen to reduce it. Each side adjusts independently. When empty, the springs remain dormant and do not affect the factory ride quality of either platform.

Important notes on Tundra fitment: the 985 is for the 2nd-generation Tundra (2007-2021) only and does not fit the 2022+ 3rd-generation Tundra, which switched to a coil spring rear suspension. Built at Hellwig's ISO 9001:2015 certified Visalia, California facility and backed by a Lifetime Warranty for the life of the vehicle.