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).
1 Also look for instructions on how frequently to change your transmission fluid. 2  While you can add fluid when it gets low, many car manufacturers recommend a transmission fluid change every 30,000 to 100,000 miles (48,000 to 161,000 km), depending your car.