SwRI: Mack T-12 test simulates heavy-duty, on-highway truck operations

	In this 300-hour procedure, the first 100 hours are at rated speed and power to generate soot. Then, in the last 200 hours, the engine is over-fueled at peak torque rpm to maximize the wear rates on the rings and liners.

The Mack T-12 is a procedure that evaluates an oil's ability to minimize wear of the following in engines with exhaust gas recirculation (EGR):

• Cylinder liner

• Piston rings

• Bearing wear

The Mack T-12 is part of the API CJ-4 performance category of engine oil procedures, and it simulates heavy-duty, on-highway truck operations after 2007.

Mack T-12 Procedure Equipment and Procedure

The engine used in the Mack T-12 procedure is a modified Mack E7 E-Tech 460 rated at 460 bhp and 1,800 rpm, with EGR and 2002 low-swirl with combustion system.

In this 300-hour procedure, the first 100 hours are at rated speed and power to generate soot. Then, in the last 200 hours, the engine is over-fueled at peak torque rpm to maximize the wear rates on the rings and liners.

Procedure Results

At the end of the Mack T-12 lubricant procedure, the following criteria are evaluated:

• Piston ring wear

• Cylinder liner wear

• Lead bearing corrosion

• Oil consumption

• Oxidation

	Mack T-12 procedure results are monitored and evaluated based on pass/fail criteria listed in chart below.

Used oil analysis includes:

• Viscosity at 100°C

• Soot

• Total base number (TBN)

• Total acid number (TAN)

• Lead content

• Fourier Transform Infrared Spectroscopy (FTIR) oxidation

Pass/Fail Criteria

Pass/fail criteria include:

For more information about the Mack T-12 procedure capabilities at Southwest Research Institute (SwRI) or how you can contract with SwRI, please contact Ryan Johnson at rjohnson@swri.org or (210) 522-2892.