Navigator Clean

Lincoln Navigator transmission help, please!!!?

The transmission it's pulling too hard from first to second gear only on my 1998 Navigator,i checked the oil and it looks very clean (red), also the level is fine too, it start happening a week ago, from one moment to another,what could it be the reason why?

It could be many things as your transmission has electric vaccuum and hydraulic controls. The first question is when was the tranny services last. A clogged filter "might" cause this so if you haven't had a service in the last 25,000 miles or more you could give it a shot, maybe you'll get lucky. If this isn't the case then get it to a good tranny shop and have them diagnose the problem. I could be something cheap like a vaccuum module or electronic actuator. Do you have a check engine light on? If your vehicle's computer reads the tranny they will be able to scan it and give you a firm idea of what's going on inside. Best of luck.