Tandems Won't Slide

More air?

Had this problem during my d seat training. prime road assist told us to put the blue line on red trailer port and release both breaks this gives the emergency breaks more air to hold the wheels. Also as suggested here by several people spray the rails with your favorite lube.

Or something, I forget exactly how it was explained. I just know it works, and doesn't require me to carry wheel chocks to fix tandems that wont slide.

More air?

Had this problem during my d seat training. prime road assist told us to put the blue line on red trailer port and release both breaks this gives the emergency breaks more air to hold the wheels. Also as suggested here by several people spray the rails with your favorite lube.

Or something, I forget exactly how it was explained. I just know it works, and doesn't require me to carry wheel chocks to fix tandems that wont slide.

"Emergency Brakes" are actually spring brakes - usually on only one axle of the tandem set. When the air is applied to the Emergency (red) line by pressing in the trailer supply, it supplies air, that compresses the spring in the chamber and releases the shoes from the drums. The blue line, is where air flows to the brake air chambers to actuate the brakes when you hit the pedal (or apply the trailer brake/trolley bar if equipped).

By connecting the red line from the tractor to the blue line on the trailer, and pushing in the tractor air supply button - you are sending pressure to apply the brakes - ON TOP OF the spring brakes (which stay applied also, since you aren't releasing them by supplying air on red (emergency) gladhand connector on the trailer.

BUT - if the slack adjusters are broken or need adjustment - the brakes STILL won't lock...

Rick

Along with those rocks you got in the tractor, stop and get a can of PB Blaster. Next time spray it in the channel for the tandems. That stuff fixes everything... Dry gladhand seals? Spray it.. Something won't move? Spray it.. Pins won't retract spray it... Then beat it with a hammer. Step two will still work but it's easier if you spray it first. A little lube goes a long way.

I sure wouldnt spray ANYTHING on the slider. It will make it worse in the long run. Just get it to slide, then, move it occasionally so it will not sieze up.

"Emergency Brakes" are actually spring brakes - usually on only one axle of the tandem set. When the air is applied to the Emergency (red) line by pressing in the trailer supply, it supplies air, that compresses the spring in the chamber and releases the shoes from the drums. The blue line, is where air flows to the brake air chambers to actuate the brakes when you hit the pedal (or apply the trailer brake/trolley bar if equipped).

By connecting the red line from the tractor to the blue line on the trailer, and pushing in the tractor air supply button - you are sending pressure to apply the brakes - ON TOP OF the spring brakes (which stay applied also, since you aren't releasing them by supplying air on red (emergency) gladhand connector on the trailer.

BUT - if the slack adjusters are broken or need adjustment - the brakes STILL won't lock...

Rick

Yea, this right here. If nothing is broke and your rails are just stuck you can use this to force a slide without having to find some rocks or something else to chock your wheels. If something is broke thats what you're supposed to be looking for in your pre and post trip inspection. I also do an inspection on my trailer when I hook up or disconnect from it as required by Prime. Even if your company doesn't require it though it's a good practice to be in anyhow.