A.
DGR 4.2 (blue pages) carry 3 entries for Tire Assemblies. All are shown in thin print.

(1)Tire assemblies, inflated above maximum rated pressure are forbidden for transport. They can be airlifted as non-dangerous goods if they satisfy SP A59.
(2)Tire assemblies, inflated, unserviceable, damaged or above maximum rated pressure are also forbidden, but if SP A59 can be satisfied, they can be air transported as non-dangerous goods.
(3)Tire assemblies, serviceable, inflated to pressure not greater than their rated inflating pressure are not restricted.

Special Provision A59 reads:

?gA tyre assembly unserviceable or damaged is not subject to these Regulations if the tyre is completely deflated. A tyre assembly with a serviceable tyre is not subject to these regulations provided the tyre is not inflated to a Aug pressure exceeding the maximum rated pressure for that tyre. However, such tyres (including valve assemblies) must be protected from damage during transport, which May require the use of a protective cover.?h

Furthermore, DGR 3.2.2.4.2 states: Gases of Div. 2.2 are not subject to these Regulations when containing the following:

(c) tyres which meet the provisions of SP A59;?h

As stated above, tire assemblies whether they are new or used, or whether they are serviceable or unserviceable May be transported as ?gNot Restricted?h if the tire is deflated to a pressure lower than the maximum rated pressure for that tire. There is no need to deflate them completely to 0 PSI.