Peterbilt 330/335/337 Engine Parts & Cooling

Frequently Asked Questions About Peterbilt 330/335/337 Engine Parts & Cooling

What years and engine models are compatible with these cooling parts?

Our Peterbilt 330/335/337 cooling parts are designed for models from 2005 to present. Most radiators and cooling components fit Caterpillar C7, Cummins ISB/ISC/ISL, and Paccar PX-6/PX-7/PX-8 engines. Always verify your specific engine model and serial number before ordering, as some years had mid-year changes. For example, 2007-2010 models with EPA emissions may require different radiator configurations than pre-2007 trucks.

Are aftermarket radiators as reliable as OEM parts?

Quality aftermarket radiators from trusted manufacturers like Dura-Lite, APDI, and Spectra Premium meet or exceed OEM specifications. These units feature aluminum cores with reinforced tanks and typically carry 1-2 year warranties. The main differences are price (30-50% less than OEM) and availability. Many customers report 5+ years of reliable service with proper maintenance. Avoid budget brands under $400, as they often use thinner materials and inferior welding.

What are the most common installation challenges?

The biggest installation challenges include: (1) Accessing lower radiator mounting bolts - you'll need to remove the front bumper on most 335/337 models, (2) Proper coolant bleeding - these engines require specific bleeding procedures to prevent air pockets, (3) Fan shroud alignment - aftermarket radiators may require minor shroud modifications, and (4) Hose fitment - some aftermarket units have slightly different inlet/outlet positions requiring longer hoses or elbows. Budget 4-6 hours for DIY installation.

How do I identify which water pump I need?

Water pump identification depends on three factors: engine type, belt configuration, and inlet direction. Caterpillar C7 engines use either a gear-driven or belt-driven pump - check if you have a serpentine belt system. Cummins ISB/ISC pumps vary by year: 2003-2007 use a different casting than 2008+. Look for the part number cast into your current pump housing, or provide your OEM to ensure correct fitment. Mixing pump types will cause immediate overheating.

What maintenance items should I replace during cooling system service?

When servicing your cooling system, replace these critical items: thermostats (use only OEM-spec 180?F or 195?F as specified), radiator cap (must match system pressure rating - typically 15-16 PSI), upper and lower radiator hoses, heater hoses if cracked, coolant overflow bottle if yellowed or cracked, and all hose clamps with constant-torque style clamps. Use only heavy-duty diesel coolant with proper SCA additive levels. This preventive approach typically adds $150-200 to your parts cost but prevents roadside failures.