I have towed with my DII only a handful of times in my 21 years owning it, never with any problems.

But in planning a possible tow from Atlanta to Charlotte at the end of next month, I reviewed the towing section of the Owner's Handbook and ended up confused. I pasted a screenshot below of the relevant page.

What I don't understand is the difference in meaning between rows 1 and 4 of the table. If the max capacity on-road in high range is 5500 lbs, what is the meaning of Row 1, Trailer without brakes, 1653 lbs.?

 

I think rows 2-5 assume that your trailer is equipped with brakes.

 

Exactly, trailers without trailer brakes. I have pulled DIsco's with Disco's on a uhaul trailer. A little squirrely over 65 but otherwise fine.

 

Okay. That makes sense, although it could have been written more clearly.

It's been several years since I rented a trailer, and because my truck doesn't have an electric brake controller I was wondering how U-Haul rented a trailer to me.

And then I remembered surge brakes, which are on U-Haul trailers. I'd forgotten all about surge brakes. So I'll be good to go with the U-Haul 6x12 trailer, if needed.

 

I recently towed about 5,000 pounds, with another 750 lbs in the vehicle, from Claremont California to Chattanooga Tennessee. If you plan to tow any real weight, install a brake controller, relying on surge brakes can be dangerous.
I accidentally turned my trailer controller down to the minimum and nearly rolled into an intersection trying to stop, from 20 mph, till I manually engaged the brake controller.
Braking without a trailer brakes does not work well.
Installation of a brake controller is neither that hard nor expensive..

 

I've had nearly 7,000# behind a disco. Around 5000# w/o trailer brakes. It was slow going, but the biggest thing is realizing your stopping and turning limitations. If you know how to pull a trailer safely, trailer brakes *can* be optional to a certain point. Only if you're experienced and comfortable with your limitations, though. I tow a ton, and none of my vehicles have brake controllers. When I pull something with surge brakes though, the added help is nice. It's all about knowing your limitations, and being willing to leave adequate stopping distance and travel adequately slow depending on terrain, traffic, and weather. I also tow pretty minimally with the Disco's any more since I now have trucks and full size SUVs to fill that roll when needed, but if it were my best option I wouldn't hesitate to again.

 

Surge brakes is the name for a hydraulic braking system installed directly on the trailer which takes input from the tongue to apply trailer brakes VS electric trailer brakes. If a trailer has surge brakes, then having an electric brake controller will not make any difference because there are no electronics on the trailer to interface with.