I'm getting a red line over my front right wheel in access mode on my nav screen. Also my truck drops down to access mode, suspension faults pop up when I drive my car about 20-30 miles. This only seems to happen on the highway. Can this be possibly related to a bad front sensor?

 

Yup, good diagnosis. Chances are you have a bad height sensor. If you get into the mud and dirt, you might crawl under it and ensure it's not caked up with mud or something.

Drive around with the Nav screen and keep and eye on which wheel might be going crazy. You might also check your brake light switch, and bulbs if it is happening during stop and go traffic. Don't use non-LR bulbs, and when you install bulbs, the element should be vertical.

Also-- check your battery, that can also cause it, if it is bad/going bad.

 

If I replace my front sensor will I need it to be calibrated or will it do it by itself? Also the red line only shows up on my nav screen when I get my suspension fault and it lowers itself to access height and when I push down on the suspension height selector.

 

It'd be a good idea to check and/or replace your brake (pedal) switch before you do the sensor. It's cheap and easy. Also, to answer your question, yes you will need to re-calibrate the EAS after you replace the sensor. If you have an IIDTool or other diagnostic tool that has that functionality, you can do this yourself.