Peterbilt 388 Leaf Springs, Hangers & Acc.

Frequently Asked Questions About Peterbilt 388 Leaf Springs, Hangers & Acc.

What are the weight capacity ratings for Peterbilt 388 leaf springs, and how do I choose the right one for my truck?

Peterbilt 388 leaf springs typically come in various weight ratings ranging from 12,000 to 23,000 pounds per axle. To select the correct capacity, check your door jamb sticker for your truck's GAWR (Gross Axle Weight Rating) or consult your owner's manual. For heavy-haul applications, we recommend choosing springs rated at least 10% above your typical loaded weight. Most 388 models from 2006-2015 use either 20,000 or 23,000-pound rated springs for the rear suspension.

Will these leaf springs fit my specific year Peterbilt 388, and are there differences between model years?

While most Peterbilt 388 leaf springs are compatible across the 2006-2015 production years, there are some variations. Early models (2006-2008) may have different bushing sizes and mounting configurations compared to later years. Always verify your truck's VIN and axle configuration before ordering. Key measurements to confirm include eye-to-eye length, arch height, and bushing diameter. Contact our support team with your VIN if you need help identifying the correct part.

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

Installing leaf springs requires proper jack stands, a floor jack capable of supporting your axle weight, and basic hand tools including impact wrenches and pry bars. The job typically takes 3-4 hours per side for experienced mechanics. Critical safety note: you must support both the frame and axle independently during installation. Many customers report needing a spring compressor for heavily arched springs. If you lack a proper lift or heavy-duty jack stands, we strongly recommend professional installation.

What's the difference between OEM-style and heavy-duty aftermarket leaf springs for the 388?

OEM-style springs match factory specifications and ride characteristics, typically using 3-4 leaves with progressive rates. Heavy-duty aftermarket options often feature 5-7 leaves, shot-peened construction, and military-wrapped eyes for increased durability. HD springs generally provide 15-20% more capacity but create a stiffer ride. For vocational trucks or those frequently running at maximum GVWR, heavy-duty springs offer better longevity. Standard OEM-style springs work well for highway applications and provide better ride comfort.

How long do leaf springs typically last, and what are the warning signs they need replacement?

Quality leaf springs on a Peterbilt 388 typically last 300,000-500,000 miles depending on application and load conditions. Replace springs immediately if you notice: sagging that causes uneven ride height side-to-side (more than 1 inch difference), visible cracks in any leaf, separated or broken leaves, or excessive squeaking that persists after lubrication. Other indicators include frequent U-bolt loosening, abnormal tire wear patterns, or a harsh, bouncy ride. Regular inspection every 50,000 miles can prevent roadside failures.