Oops

[4x4ord]

I forgot to back off the brake controller setting before sending my truck and fiver down the road with an inexperienced driver at the wheel. I was following along behind and noticed some very black long skid marks on the road just before turning into our campground. One quick look at my trailer tires confirmed my suspension.

[4x4ord]

^^^ Judging by the skid marks and worn tires it is likely that all four wheels started skidding, then just the front axle. The front tires are both shot where as I don’t see flat spots on the rears. The skid marks started out black as coal and then got just a slight shade lighter and carried on for a couple hundred feet or so. The driver said when she heard the screeching she backed off a touch on her brake application …. There was actually a 14 foot enclosed motorcycle trailer hooked up behind the fiver, which did not have power going to it’s brakes, so things could have been worse if it had decided to jackknife.

[Groover]

4x4ord wrote:

LanceRKeys wrote:
I wish my trailer brakes worked that well!

That's what you get with electric over hydraulic disc brakes .... square tires.:)

I also get strong, consistent and well modulated stops. The only time that I got flat spots on my tires was when I forgot to adjust the brakes for being unloaded. Since my electric over hydraulic brakes are on an equipment trailer there is about a 3 to 1 weight difference between loaded and unloaded so the adjustment really needs to be made. It probably wouldn't be much of an issue on a camping trailer. My only complaint about the electric over hydraulic brakes is that it does take a fraction of a second for the brakes to pump up when stopping. But that is a lot better than running red lights due to brakes not delivering when needed.

Since I have a gravel driveway I generally set my trailer brakes to skid on gravel then fine tune them on the road to match the truck brakes.

One thing to remember about daisy-chain leaf springs is that when braking they are prone to skidding the front axle. This is due the way the torque on the axles shift weight to the rear axle. This generally isn't an issue except in panic stops anyway so you are probably best off with a setting that locks the front brakes every now and then. I have pulled a trailer with only rear brakes and lifted the front axle off the ground in a hard stop. At least I got good braking effort for that stop.

[4x4ord]

LanceRKeys wrote:
I wish my trailer brakes worked that well!

That's what you get with electric over hydraulic disc brakes .... square tires.:)

[LanceRKeys]

I wish my trailer brakes worked that well!

[Crespro]

4x4ord wrote:
After setting the type of brakes you have (electric or electric over hydraulic) you can adjust the trailer brake gain setting. You should probably start with your controller set at about 6. At about 20 mph slide the manual trailer brake lever fully to the left …. If the trailer tires lock up on dry pavement back the setting off … it the tires rotate freely turn the setting higher. The goal is to adjust so that maximum braking can be achieved without wheel lock up. I am often at about 17000 lbs so a little over my trailer’s GVWR and my wheels will lock up at 6.5 on pavement.

Thanks. Good info. I will do this test.

[4x4ord]

After setting the type of brakes you have (electric or electric over hydraulic) you can adjust the trailer brake gain setting. You should probably start with your controller set at about 6. At about 20 mph slide the manual trailer brake lever fully to the left …. If the trailer tires lock up on dry pavement back the setting off … it the tires rotate freely turn the setting higher. The goal is to adjust so that maximum braking can be achieved without wheel lock up. I am often at about 17000 lbs so a little over my trailer’s GVWR and my wheels will lock up at 6.5 on pavement.

[Crespro]

Hi. I have the same weight fifth wheel and run 7.0 on an F-250. Seems fine, but you suggest 6.0. I know there is a test at 20mph. Is that how you set your unit at 6.0?

Thanks!

[ACZL]

Brakes work !

[FishOnOne]

I hate it when that happens.

[JIMNLIN]

I pull several different size trailers with the same truck. I've flat spotted my 32' 5th wheel rv tires tires more that once because I forgot to back the controller off after pulling a heavier trailer.

And of course pulling one of my empty flat decks and hitting the first stop signs after pulling my rv trailer. This left long skinny black marks as the tires (no load) rode the center of the tread.
All the many rv and non rv trailers I've owned I R&R the trailers brakes with maybe heavier wire....get rid of all clamp type connectors...make solid connections....make sure each brake is receiving the correct amps/etc.
Doing so with the brake controller set high enough it can slide the tires even at max axle loads.

[jdc1]

Reminds me of the rime my nephew pulled the pin on the brake disconnect on my dump trailer. I asked why he did it. His said he wanted to see what would happen. 1/2 a block of skid marks is what happens. He never did that again. 20 years later, I gave him that same trailer.

[4x4ord]

^^^^ The brakes are releasing fine. The controller was set to 7.5 and should have been set to 6.0. I took the truck for a spin afterward and was surprised to discover how the brakes felt normal set at 7.5 during a typical brake application yet it didn’t take much more than normal effort to get the wheels to lock up.

[pitch]

valhalla360 wrote:
Check that the brakes themselves aren't the issue. Did they seize up?

Even at max and locking up when braking...they should still release once the driver takes his foot off the brakes.

Yep he sure skidded those tires for a distance. There should have been smoke rolling, he ain't got no mirrors?
Valhalla is correct though, your controller can be set to the max and this will not occur,you have a frozen brake.

[valhalla360]

Check that the brakes themselves aren't the issue. Did they seize up?

Even at max and locking up when braking...they should still release once the driver takes his foot off the brakes.