5th wheel not unlocking trailer?

Are you just grabbing the handle or do you have a J bar? You can get significantly more pulling power with a J bar.

You could also, after winding the landing gear down, drop your air bags and leave your tractor brakes released, to reduce any tension there may be between the jaws and the kingpin.

Wd40 probably isn't what you want. Having it properly greased is what you want.

 

I'd have it power washed real good by a place that uses steaming hot water. Some Streekin' Beacons will do it. Then I'd drown the jaws with diesel then grease the hell out of it. Use a grease that is good for Winter due to it getting weird when super cold. It might also need to be adjusted. If it has a threaded rod and bolt on the front of it then it's adjustable.

 

Power wash it first. If that doesn't help then it may need a new spring kit installed.

 

Avoid WD40. It is washing off the grease, which you may want, but it leaves the "washed" metal more susceptible to corrosion because it is such a thin and runny liquid. You need maintenance or proper grease.

 

And spray all the springs, levers and pivot points under the front of the 5th wheel as well. Use a dry lithium or graphite spray so it doesn't attract dirt and road grime. I use spray that is made for RV pop-outs many times. It also might be over adjusted. It may have been adjusted using an older trailer and when you hook to a newer trailer the king pin isn't as worn so it doesn't have as much slack to relieve the tension on the jaws no matter how much pressure you apply after setting your trailer brakes.

 

Squirt some diesel in the jaws and where the grease has accumulated and it will get better. I had a fifth wheel in the wintertime and you couldn"t even budge the handle and after I squirted some diesel in there it worked good even at minus 30

 

I had a problem with mine last month, couldn’t get it to release. Turned out to have a broken spring.

 

Listen to this. When I had my union job, setback axle cabover Freightliner, not old, but not new either, couldn't get away from a trailer. Old timer looking at the situation, noticed I wasn't exactly square on the trailer. He said, "straighten it out", which I did, ka-ching! Something with the worn jaws, it had to be perfectly straight. Sometimes if it's really cold, jaws will stick. Years ago, we used to douse the whole thing with fuel to loosen things up, ,,I don't recommend that today.

 

Take it to the shop. Try the J bar first, it might be jammed. I had this problem a lot. I would unhook my airlines too early without putting enough air pressure to release the fifth wheel.. problem on International trucks. You shouldn't take over 30 sec to deal with a fifth wheel. Shop!