Caterpillar’s 966M, 966M XE, 972M, and 972M XE wheel loaders have U.S. EPA final Tier 4 ACERT engines equipped with a combination of electronic, fuel, air and after-treatment components.

The XE Advanced powertrain first introduced with the 966K XE continues with the 966M XE, and the new 972M XE joins the product line. The XE technology results in 25% lower fuel consumption on average compared to machines with traditional torque converters, simplifies operation with a two-pedal design, and provides high performance at all speeds, according to the manufacturer.

The 966M and 972M powertrains have also been improved with the addition of lock-up clutch torque converters. These new torque converters have also been matched with the engine power and hydraulics to improve performance and fuel efficiency. These planetary transmissions also have a new split-flow oil system and use multi-viscosity oil, which improves fuel economy. The new features and further axle and hydraulic improvements result in 10% lower fuel consumption on average compared to the 966K and 972K.

In addition to aggregates, sand and gravel and batch plants, these models are commonly used in heavy construction applications where poor underfoot conditions make traction difficult. The new disc-type differential locks improve tractive ability in these applications and deliver increased productivity. All four models come standard with front-axle differential locks, which are manually activated by a switch on the floor. Optional fully automatic front and rear axle differential locks operate by measuring differences in axle speeds and require no operator intervention to activate. These disc-type differential locks reduce tire scuffing compared to other traction aids.

The axles contribute to lower fuel consumption due to lower oil levels and bevel gear shrouds that reduce churning losses from rotating components. They also have new external caliper disc parking brakes mounted to the input shaft of the front axles. Caliper parking brakes have higher capacity than the drum brakes used on the 966K and 972K. Since they are external, they do not have the inefficiencies of enclosed wet parking brakes due to brake discs running in oil nor is there any oil to change. The results are reduced fuel and maintenance costs. External caliper parking brakes are easily accessible for inspection and service.

The machines’ hydraulic systems also have significant design changes and customer value improvements. The main hydraulic valve is now a mono-block with an integrated ride control section. The mono-block design reduces weight, has 40% fewer leak points, and is common across all M Series models. The new ride control system now has two accumulators enabling it to be more effective over a greater payload range, increasing productivity and operator efficiency. Auxiliary third and fourth hydraulic functions can be added at the factory or in the field with the addition of a second remote valve.

Hydraulic system components are protected by full flow and kidney-loop filtration. A filter in the hydraulic tank return line filters all of the oil returning to the tank. There is also a case drain screen for additional protection, and a separate kidney-loop filter with a finer micron rating continuously filters smaller particles out of the system. This multilevel design ensures the hydraulic oil is clean and thoroughly protects the rest of the hydraulic system from contamination. A new thermal bypass valve has been added to improve hydraulic system warm-up. 

New hydraulic implement pumps continuously and automatically balance hydraulic loads with the machine performance desired by the operator. The new pumps have larger displacements for increased hydraulic flow at lower engine rpm, thereby saving fuel. Engine response is improved, as is performance at higher altitudes.

The hydraulic service center for these machines is now virtually identical to the rest of the M Series product line. This new consistent layout makes it easier for service technicians who work on a variety of M Series models.

Machine Specifications


966M / 966M XE

972M / 972M XE


Cat C9.3

Cat C9.3

Net power, hp (SAE J1349)

277 / 277

300 / 300

Operating weight range, lbs.



Bucket capacity range, yd³



Bucket pin height(std/high lift), in.



Request more information