I am have a 5-speed and been drinving most of my life. Wtf is the purpose for overdrive. My modo 5-speed or no speed.

 

Overdrive, in the 4th gen max, is available only in auto. It's a lockout of 4th gear. IF you have overdrive turned off, it will lock out fourth gear, and keep you in 3rd. If you turn overdrive on, it will then shift into 4th gear, mainly to conserve gas mileage.

 

Question is answered here.

 

pssst...5th gear is an overdrive gear...