Northern Radiator

Definitive Charge Air Cooler (CAC) Guide

Also known as Intercoolers.

Northern Radiator takes pride in its depth and breadth of it’s charge air cooler program. Northern’s charge air coolers are designed from the ground up to meet or exceed OE specs and offer superior quality throughout.


  • Over 300 models covering thousands of truck and bus applications!
  • Laser-scanned cast tanks for exact match of OE fit on every charge air cooler we develop.
  • Built brand new. No recores or rebuilt units. No core charges.

Leaking Charge Air Cooler

  • Leaks away turbo boost
  • Low or no boost means massive horsepower loss
  • Loss of boost or no boost creates more heat
  • Uses more fuel
  • Consider this: by finding and taking care of an air leak you can easily save money on fuel. Learn about our Charge Air Cooler Test Kit.

CAC Failures

  • CAC's usually are replaced every 3 to 5 years
  • 50% of all CAC failures are the direct result of failed turbo chargers
  • Heat
  • Vibration
  • Internal pressure cycling will eventually create stress cracking and metal fatigue

Common Symptoms of Failure

  • Loss of engine power
  • Increased fuel consumption
  • Elevated coolant temperatures
  • Exhaust manifold failure
  • Premature piston, ring, and valve failure
  • Turbocharger failure
  • Increased particulate levels in emissions

Cleaning CACs

Renew performance and enhance heat transfer by internally cleaning CACs

Our Cleaner:

  • Organic pine terpene degreaser & mild acid cleanert removes oil, soot and oxide from the INSIDE
  • Unique foaming action blasts away oil & oxidation
  • Extensively tested cleaner
  • Safe with epoxies, viton rubber, silicone hoses or gaskets

Before CAC Cleaner

After CAC Cleaner

Testing CACs

  • Testing CACs on a regular interval is a must
  • CACs are unlike radiators that are filled with coolant that will give visible signs of a leak
  • CACs must have a pressure test performed to confirm its integrity
  • According to most OEM specifications, CACs that show a pressure drop of greater than 5 PSI within 15 seconds when pressurized at 30 PSI should be replaced (see chart below)

Northern's CAC Test Kit (RW0090-11)

  • Use the tool to safely, efficiently, and effectivly determine whether any CAC passes or fails the manufacturer's specifications
  • Universal design compatible with most manufacturers CAC
  • 10 minutes is all it should take in most applications
  • Education and testing is the key to CAC sales

CAC Leak Test Kit

Manufacturer Acceptable Loss Timing Pressure
Caterpillar 5 psi 15 seconds 30 psi
Cummins (ISB, ISC, N14) 7 psi 15 seconds 30 psi
Cummins (ISX, M11) 5 psi 15 seconds 30 psi
Detroit Diesel 5 psi 30 seconds 25psi
Dodge 7 psi 15 seconds 30 psi
Ford 1.5 psi 60 seconds 28 psi
International 5 psi 15 seconds 30 psi
GMC/Chevy 5 psi 15 seconds 30 psi
Mack 5 psi 15 seconds 30 psi
Mercedes 5 psi 15 seconds 25 psi
Volvo 7 psi 15 seconds 30 psi

Note: Charge air coolers are not designed to be 100% air tight and leak free.


*Northern’s charge air coolers have a 2 year / 250,000 mile warranty from date of installation.