Replacement Aftercooler for Cummins B Series Engines.

Replaces Cummins Part Numbers: 3979771, 5566841, 5267875, 4302547, 3979771

Complete Assembly. What do you get? 

• When you open the box you get: 
  • Mr Cool has perfected the configuration. The housing you receive will mimic the fit and function of the unit that is currently installed.
  • This unit will mount in the exact same location using the same threaded ports as your original. This unit WILL NOT come with replacement mounting hardware. However, you will be able to reuse your current hardware without issue.
  • This part is made with OEM Equivalent Materials, Design and Manufacturing Methods.
  • Tubing used is CuNi (Copper Nickel) which is the new industry standard. This material is a significant improvement over the standard copper tubes that are on all original units. The addition of nickel to copper significantly enhances the ability to withstand corrosive environments. It forms a more protective surface film. This will help to reduce pitting, crevice corrosion, and stress corrosion cracking.
  • The Fin count is 25FPI as with the OEM
  • Mr Cools headers are made with extruded billet brass
  • This is better brass material than from other parts of the world where only one substandard brass is allowed for export.
  • Or they use machined cast headers which have a lower density likely leading to a shorter product life.
  • Using lubricant makes it easier to install the part and then remove it when doing your regular maintenance. 
  • Smaller which matches the OEM offering plus a larger cross section which may compensate for a worn housing as your system ages.
  • Although this is disregarded by some YouTube installers these stabilizers are quite important. They perform 2 functions:
  • 1. Reducing vibration at the tube header connection which has the potential of extending the cooler life and keep the area below the header from becoming embrittled. 
  • 2. Reducing air bypass at the cooler extents. 
• Aftercooler Housing
• Aftercooler Core
• A tube of lubricant and a brush for application.  
• Two sets of 0-rings (in different diameters).
• Pre-installed core stabilizers

 This is a Mr Cool (USA) marine part MRC3979771.