Because of its dependence on ATF, low fluid level can have a disastrous effect on transmission operation — and even transmission life. That’s why it’s so important to keep an eye on the transmission fluid level.
Unfortunately, in recent years, many manufacturers have started to eliminate the transmission fluid dipstick.
Called sealed units, these transmissions require a much more involved process to check fluid levels than in days gone by. The process often involves electronic testing devices, such as a computer scan tool. This puts checking the transmission fluid level beyond the capabilities of the average car owner.