Joe replied:

The biggest difference between the two is in how the braking systems react on downhill descents.

Imagine that you are on a downslope on dirt (or worse, on clay) and maybe very slightly angled across the slope. You will be in low gear (maybe low range) using engine braking to ease you down the slope. With electric brakes the trailer brakes are not on and the trailer follows the 4WD. With override brakes (whether hydraulic or not) the brakes on the trailer would be applied as you descend the slope. The possibility exists for the trailer wheels to lock and slide sideways on the clay surface, dragging the back of your 4WD with it. This is not exactly something to look forward to.

If you are never likely to get into that situation then the override brakes will be fine and less fussy to maintain. However, most people would opt for the electric brakes even at the cost of the extra maintenance.

Hope this helps.

Joe

Geoff replied:

Simon,
Three years ago I was in Alice Springs and camped next to a bloke and his wife who'd been there for a week, waiting for parts for the electric brakes on their name brand off-road camper trailer.

As a rule, electrical things don't like to be exposed to severe dust, vibration, submersion, or heat.

Hydraulic brakes are fairly simple, but require maintenance to keep the wheel cylinders and hydraulic lines in good condition.

Cable override brake seem to be the simplest, cheapest and easiest to maintain in adverse conditions (check out any boat ramp).
However, they're not very pretty and don't have the same "Gee Whizz" factor as other systems, so they won't impress your mates.

Joe replied:

Simon - You could use the reversing lock out for the brakes, but you don't always have the time or inclination. Imagine a pissing wet day and then you come down a bit of a slope on a dirt road. Not many people would jump out to lock out the trailer brakes - and then jump out later to lock them back in!

Joe replied:

Simon,

I neglected to mention the sophisticated adjustability of electric brakes providing control beyond the capability of over-ride brakes (whether hydraulic or cable) that is worth having.

There is also the fact that the electric brake controller allows the application of the trailer brakes on their own. This might sound odd, but if you have ever been overtaking a road train when your trailer suddenly decides to become the wagging tail on your 4WD the ability to pull it back into line by applying the trailer brakes without backing off on the power is a great safety feature.

I agree that there is more to go wrong with electric brakes, but it is my belief that when it comes to braking systems you should have the best, even if it does mean a litte more maintenance.

Joe

Mick replied:

Having had electric brakes on a camper for 6 years, then buying a Kimberley K with hydraulic disc brakes only to have them fall apart within 10,000ks and completly stuff the braking system, then drive another 7,000ks on rough roads without any brakes till they could be fixed properly, our next camper [ordered Ultimate] will have Electric brakes. Having to fold the flap over on the override everytime you want to reverse up an incline was a PITA. Braking that is only working on an inertia stop start system, give me electric any time.