0 0 Paccar FLEX AIR Suspension for a 2020 Peterbilt 579 Newly Listed $6,995 USD DISC BRAKE FLEXAIR SUSPENSION ASSY D40-155 2.64 RATIO. DIFFS AND HOUSINGS INV. SEPARATELY ConditionUsedFits To Make(s)PeterbiltFits To Model(s)579Will Fit Year(s)2020Part NumberFLEXAIR DISC BRAKEStock Number120125-27 MLS Number14015462CategorySuspensions Last Updated12/4/2025 LocationUcon, ID, US Sold ByHolst Truck Parts (833) 541-___ SHOWNUMBERCall Seller Email Seller Save More Info