10 Things We’re Learning About the Peterbilt 589 — Vol. 1 | Heishman AG

At the Four State Trucks facility in Joplin, Missouri, the team at Chrome Shop Mafia recently rolled one of their first Peterbilt 589s into the shop — and it’s already turning heads.

The big question surrounding the industry right now:
Can the 589 be as user-friendly and as cool as the legendary 389?

After spending time in the shop during the early stages of this flat roof build, here are 10 key takeaways from the project so far.

Flat roof Peterbilt 589 parked inside Chrome Shop Mafia installation bay in Joplin Missouri before custom visor and exhaust upgrades.

The flat top Peterbilt 589 arrives at Chrome Shop Mafia ready for its first round of custom upgrades, including a redesigned visor, exhaust system, and stainless panels.

1. The 589 Is Slowly Winning People Over

When the 589 first debuted, reactions were mixed. It’s not a 389 — and in trucking, tradition runs deep.

But sentiment appears to be shifting. With more 589s hitting the road and appearing at major events, resistance seems to be softening as drivers begin to see its customization potential.

Front view of flat roof Peterbilt 589 inside Chrome Shop Mafia shop with technician standing beside grille and factory bumper before custom modifications.

A closer look at the front of the Peterbilt 589 before upgrades begin. From the factory bumper to the grille and exhaust, this build is about to undergo a full custom transformation.

2. This Is the Future of Custom Builds

With the 389 no longer in production, the 589 represents the next chapter for show-quality and owner-operator builds.

Shops across the country — including Chrome Shop Mafia — are investing time and engineering into learning the platform because this is what they’ll be building on for years to come.

Technician inspecting side of Peterbilt 589 near air cleaner and step area before installing custom stainless panels and lighting upgrades.

Evaluating the air cleaner and step area on the 589 before designing custom stainless panels and integrated lighting. The modern cab layout means new mounting solutions and fresh engineering.

3. The Flat Roof Brings New Challenges

This particular truck features a traditional flat roof cab, which presents unique design considerations.

Unlike the Ultra Cab version (for which aftermarket visor options are already available), the flat top requires entirely new measurements, templates, and bracket systems. Nothing transfers directly from previous generations.

Close-up of Peterbilt 589 lower step and cab mount area showing curved body lines and custom stainless step panel inside installation shop.

A closer look at the lower step and cab mounting area highlights the 589’s curved body design — one of the key challenges when fabricating custom stainless panels and trim.

4. Modern Styling Means Fewer Straight Lines

One of the biggest differences between the 589 and the 389 is panel geometry.

The 589 features:

  • More curvature

  • Fewer flat panels

  • More integrated body lines

For aftermarket designers accustomed to straight stainless panels, this shift demands additional engineering and creative problem-solving.

Factory exhaust flex pipe and mounting system on Peterbilt 589 showing frame-mounted elbow and cab-mounted upper pipe inside shop.

A look behind the shield reveals the 589’s factory flex pipe setup — designed to allow cab movement, but requiring re-engineering for a clean straight-pipe custom exhaust system.

5. The Factory Exhaust System Is Complex

The exhaust setup on the 589 differs significantly from earlier models.

The system includes:

  • A roughly 7-inch elbow

  • Reduced pipe diameter sections

  • A flex (bellow-style) section hidden behind the shield

  • Multiple mounting points — some attached to the frame, others to the cab

This configuration allows for cab movement on air ride systems, but it complicates clean aftermarket pipe installations.

Close-up of factory exhaust stack and mounting brackets on Peterbilt 589 showing multiple clamps and upper cab connection point.

The 589’s factory exhaust stack features multiple clamp points and a cab-mounted upper section — a setup that requires careful redesign when converting to long drop custom pipes.

6. Re-Engineering Is Required for a Clean Look

To achieve the straight-pipe aesthetic many owner-operators prefer, the factory system must be redesigned.

That includes:

  • Removing the flex section

  • Reworking mounting points

  • Installing long drop 7-inch pipes

  • Eliminating excess shielding

It’s not a simple bolt-on swap — it’s a custom engineering project.

Factory air breather assembly mounted behind cab on Peterbilt 589 showing clamp brackets and vertical canister design.

A closer look at the 589’s factory air breather setup. The updated mounting design and clamp system mean custom panels and lighting will require new engineering solutions.

7. Air Cleaner Panels Need Custom Mounting Solutions

Unlike previous models, the 589 lacks traditional strap and bracket setups for easy air cleaner panel installation.

To add stainless panels with integrated lighting, the team must develop entirely new mounting systems — another example of how the 589 platform requires fresh thinking.

Fuel tank and sleeper panel area on Peterbilt 589 showing factory tank configuration before custom stainless panels and DEF cover installation.

The factory fuel tank and sleeper panel layout on the 589. Plans include balancing the tank sizes visually and adding stainless sleeper panels for a cleaner, more symmetrical look.

8. Fuel and DEF Tank Symmetry Matters

From the factory, this truck came with:

  • A 120-gallon tank on one side

  • A 90-gallon tank and DEF tank on the other

To achieve a balanced appearance, plans include repositioning components and covering the DEF tank to create visual symmetry — a key detail in high-end builds.

Aluminum step assembly on Peterbilt 589 showing factory tread plate steps before stainless trim and lighting upgrades.

The factory step assembly on the 589. Clean from the start — but ready for stainless upgrades and integrated lighting to match the rest of the build.

9. Stainless Cab and Sleeper Panels Are in the Works

Additional upgrades planned include:

  • Cab and cowl skirts

  • Sleeper panels

  • Integrated lighting

  • Stainless finishes

While the final parts list is still evolving, it’s clear this 589 will receive a full visual transformation.

Custom sun visor mounting brackets installed on flat roof Peterbilt 589 cab during fabrication process inside shop.

New visor brackets mocked into place on the flat top 589. Because this roofline is different from the Ultra Cab, a custom bracket system is required before the final visor can be installed.

10. Even Simple Modifications Require Extra Labor

One early example: installing visor brackets required removing the headliner.

Access to mounting points was far more involved than expected, reinforcing a broader theme of the 589 build — what looks straightforward often requires deeper disassembly and creative solutions.

Early Verdict: A Different Kind of Classic

The 589 isn’t a 389 — and it wasn’t meant to be.

It represents a more modern take on the traditional long-nose platform. While it introduces new engineering challenges for aftermarket shops, it also opens the door to new design possibilities.

If this first build in Joplin is any indication, the 589 may not just replace the 389 — it may define the next era of custom trucking.

YouTube thumbnail for Peterbilt 589 build Vol 1 at Chrome Shop Mafia featuring flat roof 589 inside shop during custom exhaust and visor installation.

Watch Vol. 1 of the Peterbilt 589 build to see the first round of modifications — from exhaust tear-down to custom visor bracket fabrication — now live on YouTube.

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