Frequently Asked Questions About International 9900/i/ix Drive Axle Springs & Hangers

Will these springs and hangers fit my specific International 9900 model year?

Our drive axle springs and hangers are designed to fit International 9900, 9900i, and 9900ix models from 1987 through 2017. However, there are variations between model years, particularly in mounting hole patterns and bracket designs. We recommend verifying your truck's VIN and existing spring pack measurements before ordering. Common variations include 3-inch versus 3.5-inch spring widths and different hanger bracket styles between pre-2000 and post-2000 models.

What's the difference between OEM and aftermarket springs, and how long should I expect them to last?

OEM springs typically use higher-grade steel alloys and undergo more rigorous heat treatment processes, resulting in 200,000-300,000 mile lifespans under normal loads. Quality aftermarket options can perform similarly when manufactured to proper specifications, often at 30-40% less cost. Look for springs made from 5160 or 51B60 steel with proper shot peening. Avoid economy springs under $150 per leaf, as these often fail within 50,000-100,000 miles due to inferior metallurgy.

Can I install these myself, or do I need special tools and equipment?

While experienced mechanics can perform this installation, it requires specific tools and safety equipment. You'll need heavy-duty jack stands rated for commercial trucks, a 20-ton hydraulic jack, spring compressors, and torque wrenches capable of 450-500 ft-lbs. The job typically takes 4-6 hours per axle. Critical safety note: improperly compressed springs can cause serious injury. Many customers find it more cost-effective to have a commercial truck shop perform the installation, which typically runs $400-600 in labor.

My truck has a heavy-haul setup - do I need different springs than standard freight haulers?

Yes, heavy-haul applications require springs with higher load ratings and additional leaves. Standard freight springs typically have 10-12 leaves rated for 20,000-23,000 lbs per axle. Heavy-haul configurations need 13-16 leaf packs rated for 30,000-46,000 lbs per axle. Using standard springs in heavy-haul applications will result in premature sagging, increased U-bolt failures, and potential DOT violations. Check your door jamb sticker for GAWR (Gross Axle Weight Rating) to determine proper spring specifications.

How do I know when my springs and hangers need replacement versus just new bushings?

Inspect springs for visible cracks, especially near the center bolt holes and eye wraps. Any crack requires immediate replacement. Measure the arch height - springs sagging more than 2 inches from original specifications should be replaced. For hangers, look for elongated mounting holes, cracks around weld points, or excessive rust penetration. Bushings typically need replacement every 150,000-200,000 miles and show signs of cracking, splitting, or allowing more than 1/4 inch of play. If only bushings are worn but springs and hangers are sound, bushing replacement alone can restore proper suspension performance.