I wasn't sure where to post this but hopefully it will save someone some heartache. I have a Thule four bike receiver rack to carry our bikes. It has the option to tilt down so you can open the tailgate. We just returned from a 1200 mile trip to Florida and back with all the bikes loaded and no issues. I left it hook up so that the next day I could go ring my new $$$ CF mountain bike. I got almost to the park and BAM looked back and no bike I stopped and the spring clip and pin were gone and the bike and rack were hanging 1 inch from the ground. No damage except the pedal was scratch up on the end. If this had happened on the interstate with all our bikes on it they would have been destroyed and the car following us too probably. Do Not Trust that pin !!! I found the pin and the clip and drilled an extra retainer hole. Now it has a retainer pin and the spring clip holding it in place and won't come out again. This is a very poor design and I will be writing the manufacturer also.