Frequently Asked Questions About Freightliner FL70-FL80 Drive Axle Springs-Hangers

What years and models are these drive axle springs and hangers compatible with?

These drive axle springs and hangers are designed specifically for Freightliner FL70 and FL80 models manufactured between 1996 and 2007. They are compatible with both single and tandem rear axle configurations. Please verify your specific axle manufacturer (Meritor, Dana, or Eaton) before ordering, as mounting dimensions can vary. Check your VIN plate or existing spring pack for the OEM part number to ensure proper fitment.

What weight ratings are available and how do I choose the right spring capacity?

Drive axle springs for FL70-FL80 trucks typically range from 12,000 to 23,000 pounds per spring. To select the correct capacity, check your door jamb sticker for the GAWR (Gross Axle Weight Rating) or consult your original equipment specifications. For tandem setups, divide the total rear GAWR by 4 to determine individual spring capacity. Common configurations include 15,000 lb springs for medium-duty applications and 19,000-21,000 lb springs for heavier vocational use.

Do I need special tools or equipment to replace these springs and hangers?

Yes, spring replacement requires specialized equipment for safety. You'll need heavy-duty jack stands rated for commercial vehicles, a spring compressor tool, and proper lifting equipment. Most installations require a torque wrench capable of 250-450 ft-lbs for U-bolt specifications. Due to the high spring tension and safety risks, we strongly recommend professional installation. If doing it yourself, always use proper spring clamps and never work under an unsupported load.

What's the difference between OEM and aftermarket springs, and which should I choose?

OEM springs use original specifications and materials, typically featuring multi-leaf progressive rate designs with military-wrapped eyes. Aftermarket options often provide comparable quality at 30-40% less cost, using similar SAE 5160 spring steel. Key differences include leaf thickness tolerances and bushing materials. For severe-duty applications or maximum longevity, OEM is recommended. For standard highway use, quality aftermarket springs from established manufacturers like Dayton Parts or Triangle Suspension perform equally well.

How can I tell if my hangers need replacement along with the springs?

Inspect hangers for cracks around bolt holes, excessive rust penetration, or elongated mounting holes indicating wear. Hangers should be replaced if you notice sagging on one side, uneven tire wear, or a gap exceeding 1/4 inch between the spring eye and hanger. When replacing springs, it's recommended to replace hangers simultaneously if they show any wear signs, as labor costs are already incurred. New hanger kits typically include Grade 8 mounting hardware and should be torqued to manufacturer specifications.