2019 Peterbilt 579 Wheel Alignment Specifications

Quick Reference: 2019 Peterbilt 579 Alignment Specs

These specifications are for a standard 2019 Peterbilt 579 with a steer axle capacity of 12,000–13,200 lbs. Always refer to the specific service information for the exact configuration of the truck you are working on, as specs can vary based on axle, suspension, and tire options.

Adjustability

Understanding which angles are adjustable from the factory is crucial for planning an alignment job on a Peterbilt 579.

• Front Axle: On a standard Dana or Meritor steer axle, Caster and Toe are the primary factory adjustments.

  • Caster is adjusted using shims or wedges at the front or rear mounting points of the leaf spring.
  • Toe is adjusted by loosening the clamp bolts on the tie rod and rotating the adjustment tube to lengthen or shorten the assembly.
  • Camber and SAI are not factory-adjustable. These angles are machined into the axle beam and steering knuckles. If camber is out of specification, it typically indicates a bent axle beam, worn kingpins, or a damaged spindle. Correction requires either parts replacement or axle bending, which is a specialized heavy-truck service.

• Rear Axles (Tandem): On the rear tandem axles, the goal is to ensure they are perfectly parallel to each other and perpendicular to the chassis centerline. The most critical angle is the Thrust Angle. Adjustments are made by loosening the U-bolts and using alignment pucks or slotted brackets on the suspension mounting points to shift the axle into the correct position. This process, often called a "tandem scrub" or "tandem alignment," is critical for minimizing tire wear and maximizing fuel economy.

Recommended Adjustment Hardware

For correcting non-adjustable angles like front camber, specialized equipment is required. Bending an axle should only be performed by experienced technicians with heavy-duty axle correction tooling.

For caster adjustments, various tapered steel or aluminum caster wedges/shims are available in different degree increments. These are inserted between the leaf spring and the axle spring pad to tilt the axle and change the caster angle.

Symptoms of Bad Alignment

Misalignment on a heavy-duty truck is not only costly in terms of tires but also impacts fuel efficiency and driver fatigue.

• Feathered Tire Wear: This is a classic sign of incorrect toe. The tire tread blocks will feel smooth when you run your hand one way across the tread and sharp the other way. This is caused by the tire being dragged sideways down the road.
• One-Sided Shoulder Wear: Significant wear on the inside or outside shoulder of a steer tire points to a camber issue.
  • Positive Camber (top of tire tilted out) wears the outside shoulder.
  • Negative Camber (top of tire tilted in) wears the inside shoulder. This is often caused by a bent axle beam from hitting a curb or pothole.
• Vehicle Pull: A consistent pull to one side is often caused by a significant cross-caster difference (unequal caster side-to-side) or, more severely, a bent rear axle causing a high thrust angle. The driver will constantly have to fight the steering wheel to keep the truck going straight.
• Poor Steering Wheel Return: If the steering wheel doesn't want to return to center on its own after a turn, it's a strong indicator of insufficient positive caster.

When to Get an Alignment

A wheel alignment isn't just for when you feel a problem. It should be a part of regular preventive maintenance and is absolutely necessary after certain service procedures.

• After purchasing new tires: Get an alignment to protect your investment and ensure they wear evenly from the start.
• After any suspension or steering component replacement: This includes replacing kingpins, tie rod ends, leaf springs, or steering gears.
• After a significant road impact: Hitting a large pothole, curb, or road debris can easily bend an axle or knock the alignment out of spec.
• During regular service intervals: Many fleets perform an alignment check every 50,00 to 60,000 miles or annually to catch issues before they cause significant tire wear or fuel consumption penalties.

Typical Alignment Cost

The cost for a commercial truck alignment can vary widely based on location and the services required.

• Steer Axle Alignment: Expect to pay between $150 and $300 for a standard front-end alignment (caster, camber check, and toe set).
• Tandem Axle (Thrust Angle) Alignment: A full three-axle alignment that includes setting the rear tandem axles can cost between $400 and $700, depending on the labor involved in making adjustments.

While this may seem expensive, it is a small price to pay compared to the cost of replacing a single steer tire (often $600+) or the fuel wasted over thousands of miles.

Find a trusted alignment shop on Repairius.