How to Lower a Mack Superliner
- 1). Locate the suspension-leveling valve on the Superliner's dashboard. The valve is a rocker switch with "Raise" printed on the upper portion of the rocker and "Lower" on the other side of the rocker.
- 2). Press the "Lower" side of the suspension-leveling rocker switch until the Superliner lowers far enough to back the tractor underneath a trailer.
- 3). Release the rocker switch to finish lowering your Mack Superliner.
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