Trailer Brake Controller Setting Preferences

[Merlintiaga]

The proper method of setting the gain is described in the owners manual. Here’s a screenshot from Ford’s 2021 F150 manual. My 2012 GMC Yukon has the same method.

[Merlintiaga]

Originally Posted by uncle_bob

Hi

A lot depends on just which controller you have. There are a lot of makes and models. Some work very differently than others.

First datapoint is: Set the thing up high and the trailer brakes will really to their thing. They just might last 500 to 1000 miles at a high setting.... maybe.

Next datapoint: If your TV brakes are big enough for the load, you may not really *need* the trailer brakes to stop when going in a straight line.

Next: If you are doing some maneuvering while braking, you do need some trailer braking to keep everything orderly ( = so the trailer doesn't come around the TV ....). Just how much is needed depends a lot on how violently you are doing stuff. Go crazy enough and no amount of braking on the trailer will help.

Next: How much does the trailer weigh when loaded and how much does the TV weigh? This overlaps a bit. If the trailer weights 2X what the loaded TV does, you may not have much choice in terms of putting on a bit of trailer braking ( and paying to have the brakes rebuilt fairly often).

While this all sounds hypothetical and theoretical, it's based on fiddling around. Starting off at 6 on my controller cost a lot of money. The costs have gone way down since I dropped back to 4 .....

Bob

Respectfully disagree with this. Having a properly set brake controller is critical to stopping in an emergency situation. The key in an emergency is stopping as quickly as possible. That means bringing all the wheels of the vehicle (both trailer and TV) to just below wheel-lock during emergency braking. Anti-lock brake systems bring the TV brakes to just below skid during heavy braking, you want your trailer to be just below skid for shortest stopping distance. The cost savings of new brake pads for the trailer are going to be far below the cost of the body shop for repairs after hitting something.

Also, the brake controller varies the level of braking based on how hard you are pressing the brake pedal. It’s not like the trailer will be stopping the TV with a properly set controller. The trailer will (essentially) stop the trailer, and the TV will stop the TV. if you set your gain too low, the TV’s brakes are doing too much of the stopping. The TV brakes will get overly hot, your stopping distances will be too long and you’ll wear brakes out in you TV much faster. There is absolutely no performance benefit to driving with lower gain than your trailer needs, but there are huge negatives for not having enough.

[uncle_bob]

Originally Posted by Merlintiaga

Respectfully disagree with this. Having a properly set brake controller is critical to stopping in an emergency situation. The key in an emergency is stopping as quickly as possible. That means bringing all the wheels of the vehicle (both trailer and TV) to just below wheel-lock during emergency braking. Anti-lock brake systems bring the TV brakes to just below skid during heavy braking, you want your trailer to be just below skid for shortest stopping distance. The cost savings of new brake pads for the trailer are going to be far below the cost of the body shop for repairs after hitting something.

Also, the brake controller varies the level of braking based on how hard you are pressing the brake pedal. It’s not like the trailer will be stopping the TV with a properly set controller. The trailer will (essentially) stop the trailer, and the TV will stop the TV. if you set your gain too low, the TV’s brakes are doing too much of the stopping. The TV brakes will get overly hot, your stopping distances will be too long and you’ll wear brakes out in you TV much faster. There is absolutely no performance benefit to driving with lower gain than your trailer needs, but there are huge negatives for not having enough.

Hi

Locking up the wheels when you slam the brake pedal to the floor is something that most modern controllers do a fine job of regardless of the setting of the controller. They aren't the dumb boxes we had a couple decades ago.

What the gain setting *does* impact is the relative braking between the trailer and TV during normal braking events.

What happens when you get a bit aggressive isn't just pad wear. The brake assemblies disintegrate inside the hub. It's not always obvious when this happens. Next up is the hub overheats within a few hours. Worst case a tire blows. The tradeoff is *not* as simple as just buying some pads.

Bob

[civeng99]

For me it depends on what feels comfortable to you as well. As you tow you decide what you like and what you don’t like.

I like the trailer brakes a little more on the grabby side. I figure I can service my trailer brakes a lot more simply and cheaply than the tow vehicle brakes.

Don’t feel like I’ve ever damaged my trailer brakes by being too aggressive.

Do what works for you.

[uncle_bob]

Originally Posted by civeng99

For me it depends on what feels comfortable to you as well. As you tow you decide what you like and what you don’t like.

I like the trailer brakes a little more on the grabby side. I figure I can service my trailer brakes a lot more simply and cheaply than the tow vehicle brakes.

Don’t feel like I’ve ever damaged my trailer brakes by being too aggressive.

Do what works for you.

Hi

Their gotcha here is that the Dexter stuff on the Airstreams isn't quite as rugged as one might like. They very much *can* be pushed into catastrophic failure mode without much effort. That's not something one typically runs into. There are lots of threads documenting this.

Bob

[dznf0g]

Originally Posted by uncle_bob

Hi

Their gotcha here is that the Dexter stuff on the Airstreams isn't quite as rugged as one might like. They very much *can* be pushed into catastrophic failure mode without much effort. That's not something one typically runs into. There are lots of threads documenting this.

Bob

Unless I have missed a lot of those documenting threads, I believe the issue with those catastrophic failures are due to the Dexter "auto-adjust" feature. Can it be aggravated by an over-aggressive controller setting....maybe and probably. As I have stated before, I am NO fan of auto adjust (at least not the current theory of operation and design). If I had that feature, I would remove the auto adjust components and go back to manual adjusting.

[WestieHouse]

The ““YMMV” acronym certainly applies to this thread! Lots of good, if somewhat varied, ideas and experiences m.

Me? I set my 2019 F-150 controller at 7.0 when towing our 25’ FC. We have about 30,000 miles on this combo including many steep grades in 49 states and most of the Canadian Provinces). (I avoid flowing lava.)

My last/recent brake checks on both the TV and AS show no unusual wear. I occasionally check wheel temperatures with a temp sensor after descending steep and/or long grades. I haven’t experienced excessive heat or imbalanced temperatures on the AS.

My style on twisty and/or lengthy descents is to periodically use my AS brakes to maintain speed as I approach a downhill curve. And I use the F-150 tow- haul mode while towing. The latter is an important piece not yet mentioned in this thread.

I rotate tires regularly and maintain correct cold pressure on all 8 tires. I check lug nut torque at least weekly when traveling lots of twisty downhills.

Finally, my weight distribution hitch is set well (as is tongue weight using a scale) and I check TV and AS weights on CAT scale or in OR on the road side.

Many things to consider!

[civeng99]

Originally Posted by dznf0g

Unless I have missed a lot of those documenting threads, I believe the issue with those catastrophic failures are due to the Dexter "auto-adjust" feature. Can it be aggravated by an over-aggressive controller setting....maybe and probably. As I have stated before, I am NO fan of auto adjust (at least not the current theory of operation and design). If I had that feature, I would remove the auto adjust components and go back to manual adjusting.

Agreed. I’m happy with vintage and basic. Basic kind of guy. I don’t see the trade off in complexity being worth the never adjust feature.

[Dick tracy]

I have the same basic rig and also travel lite, 6600lbs.I have my f150 brake set at +7

[Merlintiaga]

On my GMC Yukon Denali, I have the controller on 8. 9 locks the wheels during a rapid/ full squeeze of the controller. Less than 9, no wheel lock. Haven’t had any wheel lock issue when braking hard. When controller is 4 or lower, I need to press the pedal a lot harder to stop. Trailer is in storage now, but in March I’m going to do the controller setup (20-25 mph with a full squeeze) on wet pavement, that may bring my setting down to 7.

[ROBERT CROSS]

Originally Posted by civeng99

Agreed. I’m happy with vintage and basic. Basic kind of guy. I don’t see the trade off in complexity being worth the never adjust feature.

I adapted the the new axles AS installed 2 years ago...I took the never out and adjust if needed at Spring get-ready.
Nothing mechanical is for never.

Bob
🇺🇸

[Boxite]

Originally Posted by StuartsDad

The method I was taught and has worked for me:
All hitched up and on level surface, put TV in gear, proceed forward at idle. Apply full trailer brakes only. Rig should come to a soft but complete stop. Adjust controller accordingly.

That is a PERFECT way to test the system to determine the Tow Vehicle and Trailer Brakes are “ talking” or “communicating” with each-other….. ONLY. It does not adjust the trailer brakes to respond to the TV / Brake Controller requests.

The trailer brakes should be adjusted such that the trailer ALWAYS “drags” the TV regardless of TV braking-level…all the way to the point of lock-up…but without actually locking up the trailers’ wheels.
In order to achieve that it is better to use a dirt or loose gravel surface and …(after using the original method to confirm communication)… apply aggressive braking on a loose surface to adjust the brake controller to apply maximum trailer effort WITHOUT locking the trailer-brakes as the TV anti-skid cycles. Yes, this will take more than one attempt to reach that goal…but it will achieve the desired result.