"over-run" brakes?

While perusing a Land Rover web page, I noticed that the towing capacity of a Defender 90 is similar to that of a Jeep's except when using a trailer with "over-run" brakes, in which case the towing capacity is about 7,700 lbs (3,500 kgs).

I did a search on "over-run" brakes, and it seems there's a sensor in the trailer hitch or ball that controls the brakes on the trailer. Would this also work for a Jeep? Is anyone familiar with "over-run" brakes? It seems they're more popular in Europe than in the US.

Thanks.

Reply to
Michael White
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Reply to
Joseph Myers

Surge brakes (same as over-run brakes) are found in the USA mainly on commercial, rental and marine trailers. Electric brakes are most common on light utility and travel trailers.

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Trailer brakes techarticle

Look in any marina parking lot and all you will see are surge brakes. With stainless disc brake rotors they can be a waaay cool braking system, but lots more expensive than plain vanilla Dexter electric brakes.

For your Jeep trailer you want electric brakes, unless you plan on submerging the trailer often. You can control the trailer's behavior much more precisely and easily with an electric controller than you can with a surge brake actuator. For example, you can dial back the braking current on gravel roads or wet pavement to prevent premature lockup, and you can manually apply just the trailer brakes if you need to. Neither of these is possible with surge brkaes.

John

Reply to
John Davies

just yesterday i ordered a 7x18 haulmark kodiak

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enclosed trailer. electric brakes are included in the base price of the trailer, the hydraulic surge brakes are an addition $900+ ($600 on the 7000 gvwr trailer, but i got the 10000). as you can see in my invoice
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it was worth the $900 to me to have the convenience of the surge brakes.

i disagree completely with this statement. electric brake controllers require adjustment any time your load or the terrain) changes. yes you can get "close" with numbered settings but youll rarely set it "perfect" even if it "feels right". to much adjustment (even just enough that you dont even notice it) and you wear the trailer brakes prematurely. not enough and you wear the vehicle brakes prematurely. coming down bozeman pass at 90mph pulling 10000 pounds will require a lot more braking than slowing for traffic as you climb it. adjusting on the fly like that sucks and can rarely be done with precision the first try.

what are you talking about? "dialing" it isnt necessary at all on surge brakes because you only get exactly what you need anyway. premature lock up isnt a concern with surge brakes because the vehicle will provide less braking pressure anyway as it will also have less traction on gravel roads or wet pavement. this is the beauty of surge brakes, and this is why rental trailers are equipped with them....theyre idiot proof and require no thinking or adjustment. i could have made electric brakes work just fine but i also wanted a trailer that my wife could just hook up to and run, without have to try to teach her how to get close with an electric adjustment. besides, with the nature of my work the load would change many times throughout the day and the self adjustment of the surge was the way to go.

that said, the expense involved makes surge brakes impractical for most and anything that can be pulled by a swb jeep would probably do just fine with electrics.

Reply to
Nathan W. Collier

with surge brakes the tongue of the trailer itself is actually a hydraulic brake pedal. as the vehicle brakes, the trailer moves into the vehicle with more force, pushing the tongue in harder, thus pressing its own brake pedal. as the trailer brakes slow the trailer, the pressure against the tow vehicle is less so it releases the brake pedal completely synchronous with how hard the vehicle is braking.

"The "surge" or "push" of the trailer toward the automobile automatically synchronizes the trailer brakes with the automobile brake. As the trailer pushes against the car, the actuator telescopes together and applies the force to the master cylinder, supplying hydraulic pressure to the brakes."

most decent surge actuators have a bypass so you can back the trailer up hill without actuating the brakes.

Reply to
Nathan W. Collier

Reply to
L.W.( ßill ) Hughes III

For most electric controllers, I agree 100% - they are a PITA to adjust and even worse to use on the highway. Most controllers are a band aid fix and IMHO totally unsatisfactory for a serious tow rig. This one isn't junk - it's a great piece of equipment:

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Once you learn the necessary amperage for different conditions, it's dead simple to increase or decrease the current depending on the road surface or weather conditions.The unit shows amperage to 0.1 amp on an easily readable screen.

It actuates in a completely linear, predictable fashion since it is connected directly to the brake pedal arm and doesn't rely on an electronic timer or flakey bobbing pendulum. So a little foot pressure gets a little bit of trailer braking and a big stab gets lots of trailer braking. Its very transparent to the user.

When travelling down a steep, undulating gravel road, many trailer brakes will lock when you hit a dip or depression, surge brakes included - the trailer will shove forward on the actuator and apply too much pressure. This behavior even occurs on paved roads - it was most irritating to me when pulling my SeaRay 270 Sundancer down a perforated steel ramp onto a WA State ferry at low tide - the trailer wheels would lock up and slide since the trailer was sloping down steeply and actuating the surge brakes. Very scary when the surface was wet!!! I got a lot of hard looks from ferry workers. The Jordan would eliminate that problem completely.

With surge brakes there is NO way to tap the trailer brakes independently to stop a sway situation from worsening. You are forced to gradually slow down and hope the trailer will settle into position. An electric controller lets you tap the manual button to drag the trailer into line and settle it. A properly set-up sway control will eliminate the problem, but how many heavy commercial or boat trailers do you see with sway controls? Maybe 1 out of 1000? Mine had one....

Then we can start arguing about equalizing hitches, which are required for many vehicles to safely handle a very heavy tongue weight. As soon as you reef up on those spring bars you load the surge brake actuator at 90 degrees to its travel and it no longer operates freely - you have to learn to over-brake the truck to get the trailer brakes to come on, then you have to accelerate hard briefly to get the brakes to release. The surge brake manufacturers acknowledge this situation and even advise against using an equalizing hitch. This is one reason heavy travel trailers don't generally use surge brakes.

Yep, I agree completely.

I have towed surge brake equipped heavy (9000 pound+) trailers many miles in mountain terrain. I have also towed lighter (7000 pound minus) trailers with electric brakes. I would quickly choose surge brakes over electric for really heavy highway-only towing. I would upgrade to stainless disc brake rotors with a free-backing solenoid for _any_ sized boat trailer that sees salt water.

For any non-marine trailer under 3 tons that will see rough roads I would always choose electric brakes with a Jordan controller. For off road towing there is no choice other than electric for total control of the trailer in sticky situations. The first time you look in the mirror and see the trailer trying to jack knife down that steep gravel embankment you will be glad you can dial back the current and control the trailer brakes with your thumb.

This has been argued for decades., and it's always fun to start it up again. Here's my present 400 pound (3000 GVW) trailer with 10 inch electric brakes:

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John Davies

Reply to
John Davies

Jeep TJs towing capacity with over-run brakes, which as Nathan said is simply a telescopic hitch which when compressed applies the brakes and which disengages when you reverse , is 2000kg. Without it, it is 2000lb. I have towed 1500kg with my twin axle braked 8' x 6' bed trailer and it is perfectly stable. Wouldn't try much more though, and not that with a single axle trailer or unbraked one..

Dave Milne, Scotland '91 Grand Wagoneer, '99 TJ

Reply to
Dave Milne

another factor to consider is tongue weight. to properly pull a 4000 pound trailer you need 400 pounds of tongue weight to prevent swaying. 400 pounds of tongue weight would make my tj pop a wheelie. :-)

Reply to
Nathan W. Collier

it looks like a good unit but unless im missing something i dont see how it corrects the weaknesses i listed.

bottom line, if you werent there to supervise/explain would you let your wife tow an 8000 pound camper from billings to helena (using the jordon brake controller) and trust that she will be able to make the proper adjustments on the fly? i think this is the biggest reason i ordered surge, so that my wife could pull it with confidence.

Reply to
Nathan W. Collier

Well, I don't like to even let my wife drive my truck, period.

I think you made the prudent decision with surge brakes, in your situation.

Knowledge is power - the thing that scares me most is clueless travel trailer owners bombing down the freeway with no concept of how their rigs behave under marginal conditions, what their trailers actually weigh and how much tongue weight they have. Or even if their brakes are working or how much air is in the tires ;(

I give them all a wide berth....

John

Reply to
John Davies

So, there's something inherently different about the Defenders? Heavier? Or ?

Thanks.

Reply to
Michael White

lol.....understood!

Reply to
Nathan W. Collier

The Defender is heavier, and has more substantial axles and a much stronger box section chassis, more akin to the Wagoneer in size.However, it still has the same short wheel base as the Jeep, higher ground clearance and a less powerful engine. It probably comes down to a less litigious attitude...

Dave Milne, Scotland '91 Grand Wagoneer, '99 TJ

Reply to
Dave Milne

And my 1984 110V8 pulled my 2000kg trailer much better than the Jeep can. OK, the Jeep can pull it fine, and with fairly effortless use of power compared to the V8 landrover, but it still can't pull it in a straight line :(.

110 = 1850kg approx. Jeep = 1500kg approx.

Mind you, the LR90 I used for a while also had no problems and it is much nearer the Jeep's weight...

I have to say I miss my 110...

Now looking at a Toyota Hilux Surf... and a Ford Explorer... can't afford another 110...

Reply to
Danny

because so many folks objected on using surge brakes over 5,000 pounds i changed my order last minute and got the electric brakes. i looked at the jordan controller but ended up getting a prodigy. if they ever catch up on production i plan on getting a brake smart system

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because it seems almost to good to be true. they currently have an 8 week wait and i couldnt wait that long. i may go ahead and order one now and just wait on it.

btw, the jeep fits!

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Reply to
Nathan W. Collier

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