One problem related to overdrive light on has been reported for the 2004 Ford Ranger. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2004 Ford Ranger based on all problems reported for the 2004 Ranger.
2004 Ranger 4x4 aod trans slipped and missed shifts while under warranty. Took to winner Ford newark DE, was told "no codes came up, it's ok". Slipping continued, got worse, now, with 40,000 miles trans will shift late to 2nd, makes the shift very roughly, then o/d light flashes and trans will not shift into od. These symptoms are the same as many of the complaints with 2003 explorer auto trans. Nhtsa should hold manufacturer accountable.