Tips

Be sensitive to new noises, vibrations and shift behavior

Transmission's should shift smoothly and quietly under light acceleration. Heavier acceleration should produce firmer shifts at higher speeds.  If shift points are erratic or you hear noises when shifting, you should have it checked out immediately.  Whining noises coming from the floorboard are also a cause for concern.  If caught early, many problems can be resolved without costly transmission overhauls. 

Maintenance

Transmission fluid should be changed periodically. Your owner's manual should give you the recommended intervals which could be anywhere from 15,000 miles to 100,000 miles.  Most transmission experts recommend changing the fluid and filter  every 25,000 miles.

Few transmissions have drain plugs to drain the old fluid. In order to get the fluid out, the technician removes the transmission oil pan. Even if the transmission has a drain plug, the only way to also change the transmission filter is to remove the pan. When the pan is down, the technician can check for metal shavings and other debris which are indicators of impending transmission problems.

In most cases during these transmission services, only about half the oil is able to be removed from the unit. This is because much of the oil is in the torque converter and cooler lines and cannot be drained without major disassembly. The fluid change intervals are based on the fact that some old fluid remains in the system.