5th wheel unlocks by itself.

Sounds like its just worn out... Took to many in the hole and wore it out

 

Personally I would not pull a trailer anywhere until it is repaired.

 

You need to get out, ,crawl under and look, to make sure it is fully latched. Tug tests alone are not to be trusted.

Cold weather. The grease gets cold and the mechanism dosnt latch. Or snow on the 5th wheel raises the king pin just a little bit too high for it to latch properly.

 

Go under the trailer, shine a light up into the throat of the 5th wheel to visually inspect that it is latched around the shank of the kingpin... a tug test alone is not enough to insure a proper coupling, especially in snowy or icy conditions.
I have backed under, heard the latch sound, and tugged the trailer only to find out that the latch inside the fifth wheel was frozen open. I had to actually hit the handle with a hammer to engage the latch...

 

Bobtail to a shop this minute and get it fix.

You DO NOT want to risk a breakaway. Ive already had one and that's quite enough.

 

Go get it repaired straight away. If your equipment is unsafe to use, then you need to get it fixed.

 

A dropped trailer on a high speed stretch of road could easily cause a fatality accident, especially in the dark...

 

And may ruin your day..or i mean your next 10 years. Could be something simple as a broken spring under the 5th wheel head. Like others say..get it to a knowledgeable shop. Probably not a truck stop garage. Someone who knows what they are looking at.

 

My first company truck a newer kenworth 680 had problems with the fifth latching

The shop repaired it on 2 different occasions and it still acted up after me using it multiple times after the repairs.

It had me freaked out with me being a Noobie


Failed multiple tug tests and I was wondering if this was normal for these fifths. Thank god the Boss was in the sop when I brought it in for the third time and he overheard my complaint

He gave me my new Western Star that day

The fifth wheel on my used truck I bought is going to get a thorough inspection and rebuild.
And if the brand or condition is questionable it is getting replaced.

Only item on the truck more important than Brakes and tires.