What is the Johnny bar for?

Johnny arm, it operates the trailer brakes and only the trailer brakes independently from the tractor.

 

I've heard of guys using it for things other than the three things it is absolutely needed.
1) pulling it during pre-trip to make sure brake lights work.
2) pulling pre-trip to verify that trailer brakes are functioning.
3) using on uphill to hold the truck from rolling backwards while letting clutch out. I know that you should be able to slip the clutch while switching from brake to throttle, but hand brake makes it much easier.

 

Only time I ever saw one was in the antiques we had in school. they told us not to touch it too lol

 

I always nudged mine as the triple check that my trailer was hooked up etc.

 

You hang your headset on it.

 

Owner ops who pull company trailers use it to save the brakes on their tractors.

I use it for:

1. The 5th wheel tug (I am paranoid, so...)
2. To check tractor and trailer brake lights.
3. To slow down when a steer tire blows at highway speed (half pull to prevent from the trailer wheels from locking up). Prevents the aluminum wheel on the steer from getting chewed up. AND you can get stopped without losing control.

 

I use it when I got a heavy load and need to slide tandems

 

If you have Air Brakes Endorsement you already know the answer. Use it to check your brake lights solo, use it for your tug test, use it every time you get back in the truck to go to ensure the 5th wheel is engaged with the trailer kingpin. Swift drivers use it to hang their trash bag.

 

New Johnny bars are nerdy they spring up