Do your brakes fully lock up?

[Chasingopenspaces]

In the process of retitling my new to me trailer. The DMV wants me to pull the emergency brake cable on the trailer, and then drag it, skidding the tires. The brakes are definitely engaging but the tires don’t completely lock up. I’m wondering if it is because these large grippy off-road tires have more friction and if the electronic brakes would never be able to lock them up.

 

[Obsessed2findARuggedHybid]

Are you talking trailer brakes that are powered through your 7 pin connector to a brake controller module in your Colorado or the emergency brake cable that is hooked to your hitch to stop the trailer if you loose it off your truck?

 

[Chasingopenspaces]

Are you talking trailer brakes that are powered through your 7 pin connector to a brake controller module in your Colorado or the emergency brake cable that is hooked to your hitch to stop the trailer if you loose it off your truck?

Well, either. I believe the emergency brake cable basically maxes out what the brake controller module would activate. So either/both.

 

[ITTOG]

Mine lock up in both scenario's but I don't have oversized tires. Just adding some real world information for you to compare against. My boat trailer tires lock up as well.

 

[gendlert]

They probably should, but might not. I'm thinking your trailer shouldn't be heavy enough not to.

I have a built-in Trailer Brake Controller (TBC) on my truck, and have to adjust the gain on the controller for each trailer depending on the weight. I'm assuming your TBC would be adjustable as well. From my truck's manual (RAM 1500), here's how to get that adjustment right:

GAIN
The GAIN setting is used to set the trailer brake control for the specific towing condition and should be changed as towing conditions change. Changes to towing conditions include trailer load, vehicle load, road conditions and weather.

Adjusting GAIN
NOTE: This should only be performed in a traffic free environment at speeds of approximately 20–25 mph (30–40 km/h).

1. Make sure the trailer brakes are in good working condition, functioning normally and properly adjusted. See your trailer dealer if necessary.
2. Hook up the trailer and make the electrical connections according to the trailer manufacturer's instructions.
3. In a traffic-free environment, tow the trailer on a dry, level surface at a speed of 20–25 mph (30–40 km/h) and squeeze the manual brake control lever completely.
4. If the trailer wheels lockup (indicated by squealing tires), reduce the GAIN setting; if the trailer wheels turn freely, increase the GAIN setting.
5. Repeat steps 3 and 4 until the GAIN setting is at a point just below trailer wheel lockup. If towing a heavier trailer, trailer wheel lockup may not be attainable even with the maximum GAIN setting.

It's kinda fun.

 

[Obsessed2findARuggedHybid]

Assuming you have a mid size truck you may have an aftermarket brake controller? Same principles setting gain

 

[Buddha.]

I’ve been an rv tech for a couple years. I’ve installed dozens of brake controllers.

I’ve never seen trailer brakes lock up.

 

[Chasingopenspaces]

They probably should, but might not. I'm thinking your trailer shouldn't be heavy enough not to.

I have a built-in Trailer Brake Controller (TBC) on my truck, and have to adjust the gain on the controller for each trailer depending on the weight. I'm assuming your TBC would be adjustable as well. From my truck's manual (RAM 1500), here's how to get that adjustment right:

GAIN
The GAIN setting is used to set the trailer brake control for the specific towing condition and should be changed as towing conditions change. Changes to towing conditions include trailer load, vehicle load, road conditions and weather.

Adjusting GAIN
NOTE: This should only be performed in a traffic free environment at speeds of approximately 20–25 mph (30–40 km/h).

1. Make sure the trailer brakes are in good working condition, functioning normally and properly adjusted. See your trailer dealer if necessary.
2. Hook up the trailer and make the electrical connections according to the trailer manufacturer's instructions.
3. In a traffic-free environment, tow the trailer on a dry, level surface at a speed of 20–25 mph (30–40 km/h) and squeeze the manual brake control lever completely.
4. If the trailer wheels lockup (indicated by squealing tires), reduce the GAIN setting; if the trailer wheels turn freely, increase the GAIN setting.
5. Repeat steps 3 and 4 until the GAIN setting is at a point just below trailer wheel lockup. If towing a heavier trailer, trailer wheel lockup may not be attainable even with the maximum GAIN setting.

It's kinda fun.

Thanks, good idea to try maxing out the gain. I agree, ideally, they will lock up. planning on troubleshooting, have a multi meter on order to arrive tomorrow. I was just curious if I am pursuing an unachievable goal with lock up.

Pretty sure if it was sitting on those typical small tires coming out of Indiana it would lock up right away. Tempted to just borrow a set off my in-laws utility trailer for the test but might as well maximize my trailer’s ability to stop anyways.

My Colorado does have a built-in brake controller with gain adjustment so I’ll give it a shot and report back.

 

[Chasingopenspaces]

I’ve been an rv tech for a couple years. I’ve installed dozens of brake controllers.

I’ve never seen trailer brakes lock up.

Super helpful, thank you!

 

[Obsessed2findARuggedHybid]

I am confused to what lock up means. If one sets the correct gain the trailer brakes alone should stop the trailer without skidding the tires. At 15 mph

 

[Chasingopenspaces]

I am confused to what lock up means. If one sets the correct gain the trailer brakes alone should stop the trailer without skidding the tires. At 15 mph

The DMV wants me to drag the trailer with the brakes on and see the tires not roll at all, before they will give me a rebuilt title. Not sure how much sense that makes but it is the government after all.

 

[NatersXJ6]

You “Should” be able to lock them up on an empty trailer. I know that when I run my little trailer empty I have to run the gain at lowest setting or it will throw little clouds of smoke behind me as it gets excited about stopping. With full load I have to run gain at about the mid-range and it doesn’t quite lock up… much higher and I’m afraid to try.

What state DMV?

Do you actually have brakes on both axles? That would be rare for any trailer I’ve ever owned. Usually just 1 axle, thus the inspector will “never” see all 4 wheels drag. Edit… I thought I read 4 wheels but now don’t see it, don’t know what sort of trailer you have 😏

You might want to find a different branch office with a different inspector. Also read the motor vehicle code for your state, brake performance is probably defined in the code.

 

[NatersXJ6]

Make sure the battery in the trailer for the e-brake is in good condition and fully charged. They are usually pretty low quality batteries and fail frequently… it it can’t push (guessing here … 12-16 amps sustained) you won’t get max brake force. This should be independent from the brake controller output, so you can turn the gain up and prove the tires will lock and then still not have them lock with an e-brake.

I learned this the hard way using my breakaway as a parking brake on my car hauler for loading.

 

[Buddha.]

The way I test electric trailer brakes, at least the electric side of things, is to have a good battery in the unit and then measure how many amps the brakes pull.

I take a multi meter with an amp clamp and clamp one of wires of the break away switch. Pull the pin of the brake away switch , not too long though or you’ll drain your battery and get things too hot.

You should get a reading of 3-4 amps per brake. So 6-8 amps on a single axle. 12-14 tandem axle.

If you’re buying an amp clamp meter make sure it can measure DC amps, not just AC amps or it’s worthless.

Of course this doesn’t mean the brakes are working mechanically. You can pop the drums off and make sure the shoes aren’t greasy, that nothing is seized up, overly worn, and properly adjusted.

Proper adjustment of trailer drum brakes is its own subject. IMO the shoes should drag the drum very slightly when rotated.

Again I’ve never seen trailer brakes lock up but I’m dealing with loaded trailers with brakes on each axle.

 

[Chasingopenspaces]

for those of you interested, I ended up troubleshooting, found voltage at the brakes was good and just decided to swap out the brake assemblies instead of trying to troubleshoot the magnets, etc. One side had been over greased, and there was some grease on the pads, but after swapping out the assemblies it’s still wouldn’t completely lock up, although it would stop the whole truck in a reasonable distance, could smell the brakes. So I’m sure they were working fine, took it back to the DMV, different inspector saw them functioning and didn’t think twice about it and passed it .