I have a 92 ford ranger I would like to know the true mileage on it but it goes up to 99,999 I am the second owner but when I bought the truck mileage was not listed on title. How can I tell?

Pretty sure you are out of luck. As far as I know, ECU's don't store mileage, especially OBD 1.

If the milage was left off of the title, chances are it was over 99,999 as most states don't keep a record of miles over that. Does it look worn out? Is the rubber on the pedals worn smooth? are the floor mats worn through. There are a lot of tell tale signs to give you an idea if milage is right and how it was taken care of. Also, look for an oil change sticker on door or windshield as it usually has the last milage or the next oil change milage on it.