Slider Hitch Issue - defective

[Denfinger]

Last week, we picked up our 5ver from our Dealer who winterized and did some warranty work. We have a Reese 16K with the Kwik Slide square rail slider. Never have used the slider and pulled 6K miles last year. After hooking up at the dealership and performing the pull test with brakes, we proceeded on the interstate for 35 miles on the way home. After going through 3 red lights start and stop, and taking off on the 4th one, the slide released and the trailer slammed backwards into the maneuver position. Of course when it happen I touched the brakes and the trailer slammed back to the front. As I eased to the side of the road it slammed to the back again. I exercised the slide handle into the pull position and backed the trailer up with brakes holding. It showed green locked. Took off slowly towards home another 1/2 mile down the road it released again. Same slamming. Tried locking again and it showed locked and made home another mile. Called Reese and they gave me two or three things to check such as pin placement, springs in place, etc. and asked me to have our dealer check it out. Went back to the dealer. They locked it into position showing green with the handle and were able to push on it and it released and moved forward. They repeated it three or four more times and declared it defective, not be used again. Since we have not ever used the slide and my wife and I not ever wanting to experience this again feeling like we tempted fate and won, we asked Reese to replace the slide and all pins with the new style fixed legs and all new pins considering they were all seriously jolted. Received legs today and pins are on the way. Not sure if anyone else has experienced this but I will tell you this, it is very scary. Looking forward to a fixed leg installation. Reese was very helpful and will be retrieving the defective unit for analysis. By the way, not one item in the 5ver was in it's original place. I am sure we will be dealing with the fallout for a while. 2012 Ford F250 6.7 and Montana Mountaineer 295RKD.