The 4 State Trucks Blog

Ever wondered why your semi truck’s AC runs smoothly, or why it suddenly stops working? Your A/C receiver, drier, or accumulator is the unsung heroe of your commercial vehicle.  First off - Why maintain the upkeep of your air drier? If you can ensure that it works well, this part will serve as the filter and pressure valve to keep your truck’s AC system clean, well balanced, and safe.  Understanding the Role of AC Driers and Accumulators The semi truck’s receiver-dri …

Are you a commercial truck driver looking to customize your Peterbilt 389 truck with aftermarket accessories and parts, but don’t know where to start? This guide is here to help.  This model came out in 2006 and has been a hit with commercial drivers ever since - the latest iteration being the 2025 model year which launched 2 years prior.  Lauded as the “king of customizations” by Peterbilt inc., this model is designed to seamlessly incorporate an abundance of afterma …

When you’re driving a big rig, every part of your drivetrain matters—especially the clutch brake.  It may be a small, often overlooked component, but without it, your gear shifts from a standstill could get rough, loud, or downright damaging.  So, let’s break down what a semi truck clutch brake is, what it does, and how to keep it from wearing out too soon. What Is a Clutch Brake in a Semi Truck? A semi truck clutch brake is a circular disc made with a friction surfac …

You spend countless hours behind the wheel of your semi truck, looking at your fuel gauge, speedometer, and everything else on your dash. So when it comes to aftermarket customizations, upgrading your interior should probably be the first thing on the list.  Custom shift dash knobs. These don't just look cool—they can enhance your grip comfort and completely personalize your big rig. Here's a roundup of FIVE slick-looking semi-truck shifter knobs that'll immediately elevate your truc …

When your air brake lines get damaged, it spells bad news for you and your payload on the road.  Thankfully, having an emergency repair Quick-Fix NTA kit is essential for owner-operators on long hauls. This offers a temporary repair for the air brake, transmission, and other connector lines.  What Is the Quick-Fix® Kit? Created by Tramec Sloan (invented in 1981 in Lola, Kansas), this DOT-compliant, field-tested roadside hose fitting and fastener repair kit designed to get drivers …