Understanding the H2 locking axles

Make no mistake, the H2 is designed for SERIOUS offroad driving and comes from the factory with more locking axle and transfer case options than any American 4X4, however, few owners really understand what those four different buttons on the center console are for.

The Hummer H2 has four full axle/transfer case control regimes "4HI, 4HI Lock, 4LO Lock" and "Lock" 4LO with locking rear differential. The first (4HI) is used while driving on ordinary roads, when torque is distributed from front to rear axles in the ratio of 40%/60%. The second mode (4HI Lock) is suitable for VERY slippery surfaces, such as thick mud or deep snow. It is a true axle lock, as the differential divides torque split between the front and rear axle, with each wheel receiving the same amount of engine torque. The regime 4LO Lock" also works as the previous, with only one difference- the gear ratio is low & puts the engine to the limit in dealing with the most serious off-road encounters. Finally, "Lock" where the locking rear differential is reengaged and each rear wheel on the axle receives the same amount of torque from the engine. These systems are very expensive and one of the reasons for the high price of the H2.