There is a seal on the front of the AC compressor behind the electric clutch that can leak allowing freon and lubricant to leak out onto clutch surfaces and make the clutch slip when it engages. It requires pulling the clutch assembly apart to replace the seal and it also requires special tools to perform this operation. The system MUST be degassed to replace this seal.
Most just replace the whole AC compressor when this happens....

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Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited 
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