Frequently Asked Questions About Freightliner FLD SBA Drive Axle Springs & Hangers

What years and models of Freightliner FLD are these drive axle springs compatible with?

These drive axle springs and hangers are designed specifically for Freightliner FLD models with Set Back Axle (SBA) configurations, typically covering model years 1989-2002. The FLD120, FLD112, and FLD132 Classic models with SBA are the primary applications. Always verify your specific axle configuration before ordering, as Set Forward Axle (SFA) models require different components. Check your VIN or consult your truck's build sheet to confirm you have an SBA configuration.

Are these springs heavy-duty enough for vocational applications like dump trucks or heavy hauling?

The spring capacity varies by part number and application. Standard replacement springs typically range from 12,000 to 23,000 pounds per spring. For vocational applications requiring higher weight ratings, heavy-duty options rated up to 26,000 pounds per spring are available. Consider your typical loaded weight and application when selecting springs. Dump truck and heavy haul operators often benefit from upgrading to the higher capacity options for improved stability and reduced spring fatigue.

What tools and equipment do I need for installation, and how difficult is the replacement process?

Installation requires heavy-duty jack stands, a floor jack capable of supporting axle weight, spring compressors, impact wrenches, and standard hand tools. The process typically takes 4-6 hours per axle for experienced mechanics. Critical steps include safely supporting the frame and axle, properly compressing springs during removal, and torquing all fasteners to specification (typically 180-220 ft-lbs for spring pins). Due to the safety risks involved with compressed springs and heavy components, professional installation is recommended unless you have experience with heavy truck suspension work.

What's the difference between OEM and aftermarket springs, and how long should they last?

OEM springs are manufactured to original Freightliner specifications using high-grade spring steel with consistent heat treatment. Quality aftermarket options often match or exceed OEM specifications at a lower price point. Look for springs made from 5160H steel with proper shot peening and stress relieving. Under normal highway use, quality springs should last 300,000-500,000 miles. Vocational use, overloading, and exposure to road salt can reduce lifespan to 150,000-250,000 miles. Signs of replacement need include visible cracks, permanent sag exceeding 1 inch, or broken leaves.

Do I need to replace hangers and bushings when changing springs?

While not always mandatory, replacing worn hangers and bushings during spring replacement is highly recommended. Worn bushings cause improper spring articulation, leading to premature spring failure and poor ride quality. Inspect hangers for cracks, elongated bolt holes, or excessive corrosion. Replace rubber bushings showing dry rot, compression set, or metal sleeve separation. Many customers find complete spring and hanger kits more cost-effective than replacing components separately, especially considering labor costs for multiple repairs.