Irregular Wear Pattern Playbook: What Cupping, Rivering, Heel/Toe, and Feathering Really Mean (and What to Fix First)

If you manage a fleet (or you’re the one paying the tire bills), irregular wear isn’t just “annoying.” It’s a signal. Tires don’t randomly wear weird — they’re reporting a mechanical issue, a maintenance gap, or an operating condition that needs attention.

This playbook breaks down the most common irregular wear patterns — what they look like, what they usually mean, and what you should fix first so you stop throwing money at tires.

Why irregular wear matters

A tire wearing unevenly can:

• Cut tire life in half (sometimes worse)

• Create vibration and driver complaints

• Increase downtime (road calls, rework, re-torques, retreads rejected)

• Hide safety issues (steer tires especially)

The key is simple:

Don’t replace the tire until you identify the cause — or the next tire will fail the same way.

Quick “Fix First” Rule

If you only remember one thing, remember this order:

1. Safety / structural issues (loose parts, failed shocks, bent components)

2. Alignment (axle/steer alignment, toe settings)

3. Balance / runout / wheel end issues (bearings, hub, bent wheel)

4. Inflation + load habits

5. Rotation / maintenance intervals

Now let’s get specific.

1. Cupping (a.k.a. Scalloping)

What it looks like:

• “Dips” or “cups” around the tire

• Often feels like a rumbling noise or vibration

• You can usually feel it by running your hand around the tread

Most common causes:

• Worn or weak shocks (very common)

• Suspension components with play (bushings, torque arms, loose hardware)

• Out-of-balance wheel/tire assembly

• Excessive runout (bent wheel, bad mounting, hub issues)

What to fix first:

• Check shocks first. If the tire is “bouncing,” it’s getting hammered.

• Inspect suspension for looseness or worn bushings.

• Balance and check runout (wheel + tire) if the vehicle still vibrates.

Pro tip: If cupping is on the steer, don’t ignore it. It can quickly become unsafe, noisy, and hard to control — especially in wet conditions.

2. Rivering (a.k.a. “Washboard” wear / Ribs with High-Low Waves)

What it looks like:

• Wavy tread ribs (high-low pattern) running around the tire

• Often shows up on steer tires

• Creates a humming sound that gets worse over time

Most common causes:

• Alignment issues (toe setting is a big one)

• Under-inflation or inconsistent inflation

• Long miles without rotation (on positions that need it)

• Suspension wear (small play that causes scrub)

What to fix first:

• Verify alignment with a focus on toe.

• Confirm actual cold PSI vs. the fleet standard for the load.

• Address any steering/suspension play.

Pro tipRivering is often “slow damage” that starts small. Catch it early and you can still salvage decent life out of the tire.

3. Heel/Toe Wear (common on drive and trailer tires)

What it looks like:

• One edge of each tread block is higher than the other

• Feels like “steps” when you run your hand across the tread

• Often paired with increased road noise

Most common causes:

• Free-rolling axles that scrub slightly (trailer especially)

• Misalignment (trailer axle alignment is a huge culprit)

• Aggressive start/stop or frequent tight turns

• Low rotation frequency (tires living too long in one position)

What to fix first:

• Check axle alignment (trailer and drives).

• Review rotation schedule (or start one if you don’t have it).

• Watch for high scrub routes: city work, drop yards, tight docks.

Pro tip: A little heel/toe is normal on some applications. The question is: is it mild and stable — or getting worse quickly?

4. Feathering (usually a steer-tire red flag)

What it looks like:

• Tread feels smooth in one direction and sharp in the other

• The tire sounds louder over time and may pull

• Often seen as one side of tread blocks “shaved”

Most common causes:

• Toe misalignment (classic cause)

• Worn steering components (tie rods, drag link, kingpins)

• Incorrect camber/caster or bent components (less common, but real)

• Poor mounting/runout issues that amplify the effect

What to fix first:

• Check front-end alignment immediately (toe).

• Inspect steering linkage for play before aligning — otherwise the alignment won’t hold.

• Check for bent parts if the issue returns fast.

Pro tip: Feathering on steer tires is often the earliest warning that your front end needs attention. Don’t wait until the tire is “howling.”

Bonus: Other irregular wear patterns you should recognize fast

One-side wear (inside or outside shoulder):

• Often alignment (camber/caster) or bent component

• Can also be chronic under-inflation + curb/tight turn abuse

Center wear:

• Over-inflation for the load (tire crowns)

Both-shoulder wear:

• Under-inflation or overload (tire squats and rides on shoulders)

Diagonal wear:

• Alignment + torque/suspension issues; sometimes mixed with braking habits

A 2-Minute Fleet Inspection Routine (that catches these early)

When the truck is parked:

• Run your palm around the tread (feel for steps, sharp edges, dips)

• Look down each rib (waves, high-low, chopped blocks)

• Check for shoulder wear differences (inside vs outside)

• Confirm cold PSI (not “looks fine”)

• Note vibration/noise complaints (they’re clues)

If a driver says: “It’s starting to hum,” take that seriously — that’s usually irregular wear becoming established.

When to replace vs. when to correct and run it

Correct and keep running (often):

• Early rivering

• Mild heel/toe

• Mild feathering (after alignment + parts check)

• Minor cupping (after shocks/balance correction)

Replace sooner (often):

• Severe cupping (deep scallops)

• Steer tires with aggressive feathering or safety concern

• Any tire with exposed belt, sidewall damage, or rapid uneven wear

Safety note: If it’s a steer tire and you’re unsure — err on the safe side.

How Truck Haters helps (without wasting your money)

If you’re seeing irregular wear, the fastest way to stop the bleed is:

• Identify the wear pattern

• Diagnose the root cause (not just “swap tires”)

• Fix what’s causing the wear

• Put the right tire back in service with the right PSI and schedule

Truck Haters can help you evaluate the wear pattern, recommend the next action, and get you back on the road fast — whether it’s a mobile install or a shop visit.

Want us to take a look?Send us a photo of the tire + tell us the position (steer/drive/trailer) and what the truck is doing route-wise — and we’ll tell you what to fix first.