New Holland T8010 Manual page 1150

Section 50 - Climate Control - Chapter 2
STEP 151
Use the two hand, two wrench method to prevent
damage to the tubes and fittings when you loosen or
tighten the tube connections.
Always install new O-rings when the receiver-drier is
connected to the system. Lubricate the O-rings with
clean mineral oil prior to installation.
RD06A171
50-2-89