I have a 1991 Ford Explorer...now i just recently got this car and i'm used to driving stick shifts...so my mistake i took it for a ride in regular drive and noticed on the highway i was doing 60 mph and my tach was at 2600 rpm...so it hit me i'm supposed to be in overdrive, well i was at a light and shifted to overdrive and when i got up to 60 mph again my tach was still at 2600 rpm.

i'm wondering if anyone has any information about this. this is going to kill me seeing as i drive to work 30 miles a day on nothing but highways.

please help