2018 Peterbilt 389 Wiper Blade Sizes & Replacement Guide

Visibility is everything when you are hauling freight across the country. For a heavy-duty workhorse like the 2018 Peterbilt 389, maintaining a clear windshield in rain, sleet, or snow is a critical safety requirement. Due to its classic flat-glass split windshield design, the Peterbilt 389 uses a straightforward wiper setup, making replacements quick and easy for drivers and fleet managers alike.

Below is your comprehensive guide to the correct sizes, attachment types, and replacement steps for the 2018 Peterbilt 389.

Quick reference

Note: The Peterbilt 389 does not have a rear windshield wiper. OEM part numbers vary based on dealership and fleet configurations; rely on the standard 16-inch heavy-duty commercial size.

Best aftermarket replacements

While you can always pick up basic blades at a truck stop, investing in premium wiper blades will provide better longevity and streak-free performance, especially in harsh weather conditions. Many consumer automotive brands manufacture a 16-inch blade compatible with the Peterbilt 389's standard arms.

• Bosch ICON (Premium Price): A top-tier beam blade that applies even pressure across the flat glass of the 389. Excellent for resisting ice and snow buildup during winter hauling.
• Rain-X Latitude (Premium Price): Another high-quality beam blade. It is treated with a water-repellent coating that transfers to your windshield to help bead away heavy rain on the highway.
• PIAA Si-Tech (Premium Price): Made from silicone rather than traditional rubber, these blades are extremely durable and resist UV breakdown, making them perfect for trucks parked outside year-round.
• Trico Force (Mid-Range Price): A robust, high-wind beam blade designed to maintain excellent contact at highway speeds without lifting.
• Michelin Stealth (Mid-Range Price): A hybrid blade offering the aerodynamic cover of a beam blade with the flexibility and structural support of a conventional frame.

Attachment style

The 2018 Peterbilt 389 utilizes a traditional J-hook attachment style. This is the most universal and common wiper arm design in both commercial heavy-duty trucks and passenger vehicles. The end of the wiper arm bends into a "U" or "J" shape, and the wiper blade simply hooks into the curve and locks into place with a plastic tab.

How to install

Replacing the wiper blades on your Peterbilt 389 takes only a few minutes per side and requires no special tools:

1. Lift the wiper arm: Carefully pull the metal wiper arm away from the windshield until it locks in the upright position.
2. Remove the old blade: Locate the small plastic release tab where the blade meets the J-hook. Press or squeeze the tab, then slide the blade firmly down toward the base of the wiper arm to unhook it.
3. Position the new blade: Align the new blade's adapter with the J-hook of the wiper arm.
4. Lock it in: Pull the blade upward into the hook until you hear a distinct "click." This confirms the locking mechanism is fully engaged.
5. Test: Gently lower the arm back against the glass. Turn on your wipers with windshield washer fluid to ensure they are sweeping smoothly and secured tightly.

When to replace

For over-the-road trucks, wiper blades endure significantly more hours of use and environmental exposure than those on standard passenger cars. You should generally replace your wiper blades every 6 to 12 months.

Watch for warning signs such as streaking (leaving bands of water on the glass), chattering (skipping across the windshield with a stuttering noise), or visible cracking and tearing of the rubber squeegee.

Need wipers swapped fast? Find a shop on Repairius.