Peterbilt 379 HVAC Replacement Parts
When youâre driving a Peterbilt 379, you spend long hours behind the wheel. So staying cool in summer and warm in winter isnât a luxuryâitâs a must. Our lineup of Peterbilt 379 HVAC parts helps you maintain total climate control no matter what the weather or haul throws your way. Whether you're replacing a worn-out Peterbilt 379 AC compressor and an Peterbilt 379 ac condenser, upgrading your HVAC control module, or tracking down a hard-to-find heater box, weâve got you covered.Everything You Need for a Comfortable Cab
This product lineup includes dependable aftermarket solutions for the full Peterbilt 379 air conditioning system, including: - Peterbilt 379 HVAC box replacements and rebuilds. - Blower motors, heater cores, and AC lines on the Peterbilt 379. - AC control panels and HVAC control modules for better in-cab function. - Expansion valve parts, pressure switches, and threaded accumulators. - Sleeper evaporators to keep your rest space just right. - Heavy duty AC compressors designed for commercial long-haul durability. Need parts for related models like the 357, 378, or 385? Weâve stock cross-compatible HVAC components ready to ship.Why Choose Aftermarket 379 HVAC Components?
- Restore Pressurization: Fix leaking heater cores and cracked AC lines to maintain a sealed, pressurized cab environment.
- Sleeper Comfort: Specialized sleeper evaporators and APU-compatible components for comfortable rest periods without idling.
- Defrost Reliability: Ensure your windshield stays clear with high-output blower motors and reliable heater control valve actuators.
- OEM Compatibility: Our parts are designed for a "guaranteed fit," replacing common OE numbers like 18-04331 and B20011S.
Find Peterbilt AC Parts & Heating at 4 State Trucks
Get everything you need to maintain your heating and cooling system in one place, from blower motors, air filters, and refrigerant cycle components to APUs and thermostat switches. Find it at 4 State Trucks.Frequently Asked Questions About Peterbilt 379 Heat & AC Parts
What years and models are compatible with your Peterbilt 379 HVAC parts?
Our heat and AC parts are designed to fit Peterbilt 379 models from 1987 through 2007. Most components are direct replacements for factory installations, including both standard and extended hood models. However, some aftermarket modifications or custom sleeper configurations may affect fitment. We recommend checking your OEM or calling our technical support team at 1-888-875-7787 if you have a modified truck or are unsure about compatibility.
How difficult is it to replace the heater core or evaporator in my 379?
Replacing the heater core typically requires 4-6 hours of labor and involves removing the dashboard panels and HVAC box. The evaporator replacement is more complex, requiring 6-8 hours and evacuation of the AC system. Common challenges include accessing mounting bolts behind the dash and properly sealing the HVAC box during reassembly. While experienced mechanics can handle these repairs, we recommend professional installation for evaporator replacements due to EPA regulations regarding refrigerant handling.
Why is my Peterbilt 379 AC blowing warm air even after adding refrigerant?
This common issue often stems from a failing compressor clutch, clogged orifice tube, or malfunctioning expansion valve rather than just low refrigerant. The 379's AC system is also prone to condenser blockage from road debris and evaporator freeze-up from moisture contamination. Before purchasing parts, have your system pressure tested and check for proper compressor engagement. Our technical team can help diagnose the issue based on your pressure readings.
What's the difference between OEM and aftermarket HVAC parts for my 379?
OEM parts guarantee exact fit and performance matching your original equipment, typically lasting 10-15 years with proper maintenance. Aftermarket options from brands like Red Dot and Bergstrom offer 30-50% cost savings and often include upgraded features like improved airflow or quieter operation. However, some aftermarket parts may require minor modifications for installation. All parts we carry meet or exceed OEM specifications and include minimum 1-year warranties.
How do I know if I need to replace just the blower motor or the entire assembly?
Test your blower motor by checking for 12V power at the connector when the fan is turned on. If power is present but the motor doesn't run, only the motor needs replacement. Signs that require full assembly replacement include damaged squirrel cage fan blades, worn mounting brackets, or excessive play in the motor shaft causing vibration. Replacement motors alone cost $50-150, while complete assemblies range from $200-400 but include new resistors and improved bearings.
