5th wheel locking jaws wouldn't close

maybe they were locked up (no pun intended) but i'd keep an eye on it or have a shop look at it maybe.

 

One time I had the kingpin trip the lockjaw without catching it because the trailer was just a wee bit too high. Talk about a mess getting it to unlock without the kingpin!

 

I've had that happen a time or 2. The best I could figure was that the kingpin just wasn't hitting the jaws just right.

 

dont leave us hanging.....how did you unlock it?

 

I've had it happen randomly here and there but have never had a problem in the long run with it. For awhile I was dropping and hooking over 10 times a night and it would happen from time to time. Come to think of it, it was always the same trailer that did it. Lowering it always worked for me. I wouldn't be overly worried about it.

It's something I check on every single hook up visually though. I get under the trailer every time to see how the kingpin and jaws are locked up together. I'll never leave that one to just a tug test. I've had one lock sitting high and it held under a tug test. I caught it though when I inspected it visually.

 

While pulling on the unlock I pulled on the jaws and got them to open.
I got incredibly greasy but got the job done!

 

I would have it looked at regardless but make sure its lubed and recheck height of trailer and would back up slowly again but dont hook it. get as close as possible, set the brake, get out and look to see if you arent jamming against something before the kingpin gets into the jaws. Once you finally figure out whats going on or it decides to lock then make dang sure it is.

 

I drive a Freightliner Cascadia and the 5th wheel on it is real touchy. The truck sits lower then most so I always have to check before backing under. Still at times I get out and check and there doesn't seem to be a gap between the plate and the 5th wheel but it won't lock. If I get out and lower it most of the time it does. I have had times where it doesn't but if I go out and push the release up then rock forward and back it does. Don't know why but it works.

 

i had one time the trailer was set too high and with the pin style landing gear not the jack type backed up everything looked ok went to back under it and the king pin came over the top of the 5th wheel plate and got stuck over the back side of the 5th wheel. cold blowing snow and dark, it was so much fun.

i probably woulden't think too much of the jaws not locking the first time around that's why we do tug tests. i would think lowering would do more good than raising though. i always try to set trailers a little low when i drop so they lift a inch or so as they come up the 5th wheel. if too low you can always drop your airbags. so when i drop i don't crank the jacks all the way to the ground