Peterbilt 379 Charge Air Coolers

Frequently Asked Questions About Peterbilt 379 Charge Air Coolers

What does a charge air cooler do on a Peterbilt 379?

The charge air cooler, also called an intercooler, cools the compressed air coming from the turbocharger before it enters the engine. Cooler, denser air improves combustion efficiency, helps the engine produce more power, and reduces strain on internal components. On the Peterbilt 379, it is mounted in front of or alongside the radiator so airflow from the grille passes through it before reaching the cooling system.

How do I know if my charge air cooler needs to be replaced?

Common signs of a failing charge air cooler include a noticeable loss of engine power, increased black smoke from the exhaust, higher than normal boost leak alarms or codes, oil residue around the cooler fins or end tanks, and visible cracks, dents, or corrosion on the core or seams. If you notice any of these symptoms, it is worth inspecting the unit closely or having it pressure tested for leaks.

Will a replacement charge air cooler fit my Peterbilt 379 without modification?

Fitment depends on the model year and original equipment configuration of your truck, since Peterbilt 379s were built over a long production run with some variation in cooling system layout. We recommend checking the listed year range and dimensions on each product page and comparing them to your existing unit before ordering, especially mounting points and inlet/outlet hose connections.

What materials are these charge air coolers made from, and does that affect durability?

Most charge air coolers for the Peterbilt 379 are constructed with aluminum cores and end tanks, since aluminum offers good heat transfer along with resistance to corrosion. Some units use welded aluminum end tanks for added durability, while others may use a plastic composite tank in certain applications. Aluminum core and tank combinations are generally preferred for heavy duty, high vibration environments like long haul trucking.

Can I install a charge air cooler myself, or should I have a shop do it?

Installation involves draining coolant if the radiator needs to be removed for clearance, disconnecting boost hoses and clamps, unbolting the mounting brackets, and swapping in the new unit before reconnecting everything and checking for leaks. Many experienced DIY mechanics handle this job with basic hand tools, but if you are not comfortable working around pressurized boost lines or do not have a way to properly pressure test the system afterward, having a qualified diesel shop complete the install is a safer option.