i have a 91 explorer with automatic trans. stock gears and 31-10.50 tires. at 70 mph i am running about 3,000 rpm, is this normal, or am i just used to my mustang that ran about 2,000 at 70 mph thanks

Is that in drive or overdrive? and what are your stock gears? (axle code on the driver's door sticker)

that is in overdrive but i dont know what my stock gears are im in class right now so ill have to check latter thanks

Did you correct your speedo when you went to larger tires? If not, you're probably going about 75 when your speedo says 70.

i did not correct my speedo thanks but i better get back to class thanks

I'm assuming you have 3.73 gears. If so, your torque converter may not be locking.

The next question after that will be, "Is it shifting into 4th gear?" Easiest way to answer that will be to perform the following road test. While cruising at highway speed, manually shift the transmission from OD to D and back and see if you can feel the transmission shift.

thanks ill check it out after class and get back to you guys latter thanks again