Hellwig 3510 LP-35 3500 lb Helper Spring SRW Chevy/GMC/Dodge/Ford Truck/Van/SUV

Vehicle Fitment

• Ford (pickups): 1973-1976 F-100; 1975-1976 F-150; 1973-1976 F-250 - SRW only, 2WD/4WD
• Ford (vans): 1996-2014 E-150 (Econoline, Club Wagon, and E-150); 1975-2012 E-250 (Econoline, Club Wagon, and E-250); 1975-2012 E-350 (Econoline, Club Wagon, and E-350 Super Duty) - SRW only
• Chevrolet (pickups/SUVs): 1973-1974 C30/K30; 1975-1986 K5 Blazer, C30, K30; 1969-1994 Blazer; 1969-1986 C10/C20/K10/K20 Suburban; 1988-1998 C1500/C2500/C3500/K1500/K2500/K3500; 1987-1991 V-Series Suburban; 1992-1999 C1500/C2500/K1500/K2500 Suburban; 1995-2001 Tahoe; 2000-2001 Suburban 1500/2500; 1999-2000 Cadillac Escalade; 2000-2007 Silverado 1500; 2001-2006 Silverado 1500 HD; 2007 Silverado 1500 Classic - SRW only, 2WD/4WD
• GMC (pickups/SUVs): 1973-1974 C/K Series pickups and Suburbans; 1975-1978 C/K Series pickups and Suburbans; 1977-1978 K35; 1979-1998 C1500/C2500/C3500/K1500/K2500/K3500; 1979-1999 C1500/C2500/K1500/K2500 Suburban; 1987-1991 R/V-Series Suburban and pickup; 1992-2001 Yukon; 2000-2001 Yukon XL 1500/2500; 2001-2007 Sierra 1500; 2001-2006 Sierra 1500 HD; 2007 Sierra 1500 Classic - SRW only, 2WD/4WD
• Dodge (pickups/vans): 1960-1974 W100/W300 Series; 1975-1989 W100; 1981-1993 W250; 1971-1974 B100/B200/B300 Van; 1975-1980 B100/B200/B300; 1981-1994 B150/B250/B350; 1995-1998 B1500/B2500 - SRW only, 2WD/4WD

Fitment Notes

• MOUNTING KIT REQUIRED - SOLD SEPARATELY: The Hellwig 3510 is the spring leaf assembly only. An LP Mounting Hardware Kit must be purchased separately and is required for installation. Compatible mounting kits for this application are #25250 (for 2.5" wide springs, GM/older Ford trucks) and #25351 (alternate GM/older application). Contact Hellwig at 1-800-HELLWIG (435-5944) to confirm the correct mounting kit for your specific vehicle.
• SINGLE REAR WHEEL (SRW) APPLICATIONS ONLY - this kit does NOT fit dual rear wheel (DRW / dually) trucks. The LP-35 mounts over the factory multi-leaf spring pack and requires the clearance available on SRW rear axle configurations.
• MULTI-LEAF REAR SPRING PACKS ONLY - the 3510 requires a factory multi-leaf rear spring pack to mount to. Not compatible with single-leaf, composite, or independent rear suspension configurations.
• Does NOT work with factory contact overload springs. If your vehicle has factory contact overload springs, check Hellwig's vehicle fitment guide for your specific year and model before ordering, as additional steps or a different product may be required.
• For newer Ford Super Duty F-250/F-350 (2011+) and newer Ram/Dodge heavy-duty applications, Hellwig offers LP-35 variants with dedicated mounting kits (see parts #3511 and #3518). The 3510 is designed for the classic-era and early modern GM, Ford, and Dodge platforms listed above.
• The 2007 Silverado/Sierra 1500 Classic and 2005-2007 Silverado 1500 entries refer to the GMT800-based last-generation 1500 pickup, not the GMT900 redesign; confirm your model year and body style matches the classic platform before ordering.

Features

• Up to 3,500 lb. level load carrying capacity - the highest-rated steel leaf helper spring in Hellwig's lineup, designed for fleet applications, heavy commercial use, RVs, truck campers, and any 3/4-ton or 1-ton SRW vehicle that consistently operates at or near its GVWR.
• Progressive rate design - completely transparent during unloaded or lightly loaded driving, engaging progressively as the factory leaf pack compresses under load. Preserves factory ride character when empty; firms and controls progressively as weight increases.
• 4-leaf multi-leaf stack construction delivers maximum bilateral support across the full width of the rear axle - providing superior load stability, reduced body roll and trailer sway, and consistent side-to-side leveling even under the heaviest sustained payloads.
• Fully adjustable load rate using the LP mounting hardware U-bolts - independent left/right adjustment for correcting uneven loads from off-center cargo, upfitter bodies, truck campers, or heavy towing configurations.
• Each spring leaf is hot-formed and heat-treated from ASTM 5160 alloy spring steel for maximum strength, fatigue resistance, and long-term durability under sustained heavy-duty use.
• Black powder coat finish over all steel components for corrosion resistance in road salt, grease, and wet-weather underbody environments.
• Eliminates rear-end sag, squat, and body roll that compromises headlight aim, front-axle traction, steering precision, and brake performance - critical for work trucks, fleet vehicles, and tow rigs regularly loaded at capacity.
• Reduces leaf spring wrap-up and axle hop under hard acceleration with a heavy load - important for diesel-powered trucks, loaded work vehicles, and any application with high drivetrain torque output.
• "Set it and forget it" design - once installed and adjusted, the LP-35 requires zero ongoing maintenance. No air bags, compressors, sensors, or electronics to fail or service.
• Bolt-on installation using common hand tools - no drilling, cutting, or permanent modifications required.
• Manufactured at Hellwig's ISO 9001 and ISO 14001 certified facility in Visalia, California - made in the USA since 1946, backed by Hellwig's Limited Lifetime Warranty against manufacturing defects.

Specifications

• Level Load Capacity: Up to 3,500 lbs.
• Spring Series: LP-35 (Load Pro 35)
• Spring Rate Design: Progressive Rate
• Construction: 4-leaf multi-leaf stack
• Spring Material: ASTM 5160 heat-treated alloy spring steel
• Spring Finish: Black powder coat
• Drivetrain Compatibility: Single Rear Wheel (SRW) ONLY - does NOT fit DRW/dually
• Leaf Spring Type Compatibility: Multi-leaf rear spring packs only
• Mounting Kit: Required - sold separately (see LP Mounting Hardware Kits #25250 or #25351)
• Drilling Required: No
• Country of Manufacture: USA (Visalia, CA - ISO 9001 / ISO 14001 certified)
• Warranty: Limited Lifetime
• Quantity: Sold as a kit (spring leaves only - mounting hardware sold separately)

Included Components

• 2x LP-35 4-leaf spring assemblies (1 per side), ASTM 5160 alloy steel, black powder coated
• Installation instructions
• Note: LP Mounting Hardware Kit (#25250 or #25351) is NOT included and must be purchased separately for installation.

Product Description

The Hellwig 3510 LP-35 Heavy Duty Load Leveler Helper Springs represent the pinnacle of Hellwig's steel leaf helper spring lineup, rated to 3,500 lbs. of supplemental rear load capacity - 40% more than the LP-25. Designed for 3/4-ton and 1-ton SRW applications where fleet trucks, commercial vehicles, RV haulers, and work rigs operate at or near their gross vehicle weight rating on a consistent basis, the LP-35's 4-leaf stack construction sets a higher bar for load stability than any other helper spring in the Hellwig catalog. The progressive rate design means the springs remain invisible during unloaded daily driving, activating progressively as payload weight builds, so the truck retains its normal ride character while standing ready to provide maximum support the moment the load demands it.

The 3510 uses a 4-leaf multi-leaf stack construction that spans both sides of the rear axle, delivering maximum bilateral support and exceptional resistance to body roll and side-to-side sway under the most demanding loads. The required LP Mounting Hardware Kit - sold separately in configurations #25250 and #25351 for the GM and older Ford/Dodge applications this kit serves - provides vehicle-specific brackets, U-bolts, and hardware that mount without drilling and allow independent left/right load adjustment for correcting uneven loads from camper placement, upfitter bodies, or asymmetric cargo. Every spring leaf is hot-formed and heat-treated from ASTM 5160 alloy spring steel and finished in black powder coat. Once installed, the LP-35 requires zero maintenance - no air bags, compressors, or electronics to fail in the field.

The 3510 covers a vast range of domestic full-size trucks, SUVs, and vans spanning the mid-1960s through early 2000s from Chevrolet, GMC, Dodge, and Ford - including early C/K pickups, Blazer, Suburban, Tahoe, Yukon, Silverado 1500, Sierra 1500, classic-era Ford E-Series full-size vans, Dodge B-Series and W-Series pickups and vans, and early Ford F-Series pickups. This kit is for single rear wheel (SRW) applications only. For 2011+ Ford Super Duty applications, see Hellwig part #3511/3518 with mounting kit #25301. An LP Mounting Hardware Kit must be purchased separately for installation. Manufactured at Hellwig's ISO 9001 and ISO 14001 certified factory in Visalia, California and backed by a Limited Lifetime Warranty.