5th Wheel Install

Installation on a 5th Wheel. 

	Kingpin Box Install For installation on a standard kingpin box, you will need to drill holes for the Trailer Hitch Sensor mounting bolts. To avoid problems, please review all of the following instructions before you begin. (click thumbnails for larger images and more info)
	Where To Install On Kingpin Box There are often other devices installed on your kingpin box such as a breakaway switch (red arrow). Mount your sensor away from other devices that might interfere with the smooth rotation of your sensor (green arrow). Also, when the trailer is aligned with your truck, you need to know whether the the stretch cord anchor point is closer to the sensor or to the kingpin – if you’re not sure, relocate your sensor to where you can be certain.
	What To Know Before You Install Make sure your mounting location will not result in your sensor (or the stretch cord) hitting anything as your trailer moves through its whole range of turning, including going through dips and over rises (for example, see red arrows). You will also need to measure the distance between the sensor’s center of rotation and the kingpin’s center of rotation (marked in green).
	Mark Vertical Line The bolts must be installed so they are one directly over the other when hitched up. The kingpin mounting plate is level when hitched, so use a right angle to mark a vertical line.
	Drill First Hole Drill a first hole for a 5/16″ bolt. Be sure to wear eye protection and hearing protection when drilling.
	Drill Second Hole Drill a second hole for another 5/16″ bolt. Be sure the hole spacing is either exactly 1½” or is 2½” or greater (but, less than 4½”). If using clamping nuts, your spacing must be the 2½” or greater.
	Holes You should now have two holes ready for mounting bolts.
	Don't Forget Lock Washers Reaching inside the kingpin box, insert two 5/16″ bolts (1¼” long or greater). Put a lock washer on the end of both bolts.
	Secure Mounting Bolts Secure each bolt with a lock washer and a nut. Your sensor mounting bolts are now installed.
	Mount Sensor Slide the Hitch Sensor onto the two bolts. Remember which holes you use on the sensor plate and then be sure to use the same holes every time so you don’t have to remeasure its location (see below).
	Secure Sensor Secure your sensor with wing nuts or clamping knobs. This so you can easily remove your sensor when not backing up to reduce the risk of theft or damage. The sensor in the picture is installed with wing nuts. If you permanently install your sensor, be sure to use lock washers.
	Sensor Installed Your sensor is now mounted.
	Splice In Flat-four Power Socket Your sensor has a flat-four connector (shown) for 12 volt power and tail-lights. Find a place to splice in a vehicle-end flat-four socket for plugging in your sensor.
	T-Bracket Installation For RV With your sensor mounted and power connected, you must next install the T-Bracket for anchoring the stretch cord. Most pickup trucks have openings in the rail of the truck bed. We suggest screwing the T-Bracket onto the end of a piece of 2×3 (1½” by 2½”) or whatever fits perfectly into one of these openings in your truck. Click image for more information.
	Attach The Stretch Cord The stretch cord is attached in the same way as it is in other installations. If your piece of stretch cord is too short, it can be extended with am small length of nylon cord (3mm or smaller diameter); just be sure the length of the stretch cord is not extended by more than 50% of its relaxed length at the point of greatest stretch.
	Measure Sensor Location Measure the horizontal distance from the center of rotation of your sensor to the center of rotation at your hitch ball or kingpin. If you are using a 5th wheel extension with a rotating turret, measure to the center of rotation of the turret. Be sure to measure with your measuring tape parallel to the ground.
	Measure Anchor Location Measure the horizontal distance from the anchor attachment point to the center of rotation at your hitch ball or kingpin. If you are using a 5th wheel extension with a rotating turret, measure to the center of rotation of the turret. Be sure to measure with your measuring tape parallel to the ground.