Calcium compounds are widely used. There are vast deposits of limestone (calcium carbonate) used directly as a building stone and indirectly for cement. When limestone is heated in kilns it gives off carbon dioxide gas leaving behind quicklime (calcium oxide).
How to Change Transmission Fluid. Transmission fluid needs to be changed from time to time in order to extend the life of the transmission, usually every 30,000â60,000 miles (48,000â97,000 km) (sometimes more â check your owner's manual for service intervals).
A variety of factors can affect the frequency with which you should change your auto transmission fluid (ATF). Different types of vehicles may have varying service intervals, and your owner's manual may specify the correct mileage for your car. Many vehicles will need their auto transmission fluid changed about every 25,000 miles (40,000 km), though some will specify a longer interval.