Peterbilt 359 Radiators

Frequently Asked Questions About Peterbilt 359 Radiators

Will these radiators fit my specific year Peterbilt 359, and what about 379 compatibility?

Our Peterbilt 359 radiators are designed to fit models from 1967 through 1987. While the 359 and 379 share similar designs, mounting points and hose connections differ between models. The 379 uses a different core support design starting in 1987. Always verify your truck's model year and check the radiator part number against your original equipment. If you're unsure, measure your current radiator's core dimensions (height x width) and inlet/outlet sizes before ordering.

What's the difference between aluminum and copper/brass radiators for my 359?

Aluminum radiators typically offer 25-30% better cooling efficiency and weigh about 40% less than copper/brass units. However, copper/brass radiators are easier to repair at local shops and handle vibration better in older trucks with worn motor mounts. Aluminum radiators require aluminum-specific coolant and can be prone to electrolysis if not properly grounded. For show trucks, copper/brass maintains the original appearance, while aluminum is preferred for heavy-hauling applications where cooling performance is critical.

Do I need to modify anything for installation, and what additional parts might I need?

Most direct-fit radiators bolt into existing mounting points without modification. However, you may need new rubber mounting cushions, hose clamps, and possibly new upper/lower radiator hoses if yours are original. Some aftermarket aluminum radiators have different inlet/outlet sizes requiring hose adapters. Plan on 3-4 hours for installation. Common issues include rusted mounting bolts that need cutting and replacing, and slight adjustments to fan shrouds on certain model years.

How many rows should I get, and what about dimpled vs. standard tubes?

Standard applications work well with 2-row radiators, while trucks pulling heavy loads or running in hot climates benefit from 3 or 4-row designs. Dimpled tube radiators increase cooling surface area by 15-20% compared to standard tubes, making a 2-row dimpled tube perform similarly to a 3-row standard. Keep in mind that more rows increase thickness, which may require fan spacers. For engines over 475 HP or frequent mountain driving, we recommend minimum 3-row or 2-row dimpled tube configurations.

What size radiator do I need - are there different options for 359s?

Peterbilt 359s came with several radiator sizes depending on engine and factory options. The most common sizes are 34" x 38" for standard applications and 34" x 42" for heavy-duty cooling packages. Extended hood models may accommodate larger 34" x 48" radiators. Measure from tank-to-tank (not including mounting brackets) and core height/width to ensure proper fit. Upgrading to a larger size requires verifying clearance for hood closure and potential air dam modifications.