hi,whats the difference beetwen d and d with a circle on transmition?
thxs

 

Are you comparing between two auto transmissions from two different vehicles? Or does your vehicle have both?

Normally the "D" with the circle means overdrive.

 

What Chameleon said. The D inside the circle is referred to as overdrive, really it lets your auto transmission go into full lock up at about 46mph, similar to a true overdrive, and become more fuel effiecient by lowereing your RPMs (it also helps reduce trans heat).

Try this, with the transmission in [D] drive at about 42-3 mph, slowly speed up, somewhere in there at 45 or above, maybe almost 50, you will feel the transmission tourque converter lock up, it is like another gear, and the RPMs will drop a bit.