Special tools required:
A desiccant insert that is in a correctly functioning, sealed heating and air conditioning system does not have to be changed at regular service-inspection intervals.
However, the dryer flask or desiccant insert must absolutely be replaced in the event of:
The desiccant insert cannot be replaced in the following vehicles:
In these vehicles, the condenser for the heating and air conditioning system must be replaced.
On this vehicle the low pressure battery must be replaced.
BMW X3 Owners Manual > Saving fuel: Tires
General information
Tires can affect fuel consumption in various
ways, e.g., tire size may influence fuel consumption.
Check the tire inflation pressure
regularly
Check and, if needed, correct the tire inflation
pressure at least twice a month and before
starting on a long trip.
Low tire ...