Which Size Brakes?

[brian_bp]

I would be very surprised if the Jeep owner's manual allowed more than 1000 lb of trailer weight without trailer brakes. Sure, there's lots of engine braking, and engine braking is good to limit speed on descents, but that's not how you stop when you really need to. Doing all of the braking for over 1000 lb of trailer is a big deal to a vehicle the size of a Wrangler. You'll only find out how big a deal if you really test it, which could be a fatal experiment.

[brian_bp]

I will have to call Dexter and figuer out weather or not the larger brakes can be fitted to the smaler axle (since they don't specify either in the catolog, I would guess against it).

The hubs are integral with the drums on these axles. The hubs must fit the bearings, and the bearings must fit the spindles. If the bearing sizes (listed in the catalog) are different for the #9 and #10 spindles (and I suspect that they are), then the #10 hubs will not fit the #9 spindles.

I agree that only 7" brakes are listed for the #9 Torflex (and same-rated leaf-spring axles) likely because they're the only ones that fit.

For the truly innovative, you can use non-braking (idler) hubs and mount separate automotive drums to them, if you can find a fit. Next challenge: will the backing plates for 10" brakes bolt onto the flange on the lighter axle? Of course, you also have to buy the lighter axle with brake flanges, but no brakes (which I believe is available by special order).

I would just use the #10 axle / 10"x2.2.5" brake stuff if I were using 31" tall tires.

[Alphacarina]

The Torflex problem in multiple-axle installations is that they - unlike leaf-spring systems with equalizer links - don't share load between the axles nicely. As a result, each axle needs to be over-spec'd to handle more than its usual share over bumps, and the load-to-capacity thing become an issue

True . . . . they don't loadshare at all - The Torflex axles ARE overspec'd which is the only thing that allows them to be used in multiples. If you run off a curb with your 11,000 pound trailer and ALL the weight is on one 5500 axle, that's OK because the axle will handle it. Dexter does not recommend triples in any case because in the same situation, you would have all of the 16,500 pounds on one tire and the axle will NOT handle that. In my situation, that wasn't a problem because the total load was only 11,000 pounds and the three axles were rated for 16,500 pounds, so no way was I ever going to hurt any of them - They would just 'ride like a truck' because they didn't have enough load on them . . . . or so I was told - Two axles carrying exactly the rated load was the much preferred scenario, so on their advice, that's what I went with

Do not 'overspec' your Torflex axle by 33% in other words, if you want it to function correctly

There's no load-sharing issue in a single axle trailer. Rubber or steel leaf, you still want the springs reasonably well matched to the load

Yes, but even more so with a torsion axle because it is still overspec'd, even in a single application. Your 1500 pound axle is still good to about 3,000 pounds without failure (in a low speed, momentary situation) and if you put an axle spec'd at 3000 pounds on your 1500 pound trailer, it will hardly ever flex so you're running down the road on basically a solid axle, with no suspension at all, since a mere 1500 pound load isn't going to allow it to function as it was designed to

Leaf springs on the other hand are much better suited to trailers which might carry varying weights, from completely unloaded to heavily loaded because the flex of the springs is more linear - 1500 pounds of load will still flex a 3,000 pound spring a good deal, while on a torsion axle it won't deflect it hardly at all

If you can get the ear of a Dexter engineer, you'll get a very frank education on what types of loads are good for torsion axles and which are better suited to springs. Used as designed, torsion axles have it all over leaf setups, but they aren't the best choice for every application and they especially aren't good if the trailer only weighs half of what the axle was designed for

Don

[Section 8]

I would be very surprised if the Jeep owner's manual allowed more than 1000 lb of trailer weight without trailer brakes. Sure, there's lots of engine braking, and engine braking is good to limit speed on descents, but that's not how you stop when you really need to. Doing all of the braking for over 1000 lb of trailer is a big deal to a vehicle the size of a Wrangler. You'll only find out how big a deal if you really test it, which could be a fatal experiment.

As in the post, its an unlimited, which is 3,500 lb towing capacity.

[Section 8]

[quote="Alphacarina
Yes, but even more so with a torsion axle because it is still overspec'd, even in a single application. Your 1500 pound axle is still good to about 3,000 pounds without failure (in a low speed, momentary situation) and if you put an axle spec'd at 3000 pounds on your 1500 pound trailer, it will hardly ever flex so you're running down the road on basically a solid axle, with no suspension at all, since a mere 1500 pound load isn't going to allow it to function as it was designed to

Leaf springs on the other hand are much better suited to trailers which might carry varying weights, from completely unloaded to heavily loaded because the flex of the springs is more linear - 1500 pounds of load will still flex a 3,000 pound spring a good deal, while on a torsion axle it won't deflect it hardly at all

If you can get the ear of a Dexter engineer, you'll get a very frank education on what types of loads are good for torsion axles and which are better suited to springs. Used as designed, torsion axles have it all over leaf setups, but they aren't the best choice for every application and they especially aren't good if the trailer only weighs half of what the axle was designed for

Don[/quote]

That was going to be the next question. The load would change as "full" it would have 400 pounds of water and fuel. For a long week end, no fuel and only half the water, 20 gallons, less cloths ect. This would be changing through the trip all the time anyway.

I guess leaves are what its going to be unless I feel feisty and design my own (or lazy and spendy) and do a Adventure Trailers independent suspension set up. I intend to have it ready to go by spring, so it might be springs anyway, no mater how feisty I get (I'm rarely spendy )

[brian_bp]

I would be very surprised if the Jeep owner's manual allowed more than 1000 lb of trailer weight without trailer brakes. Sure, there's lots of engine braking, and engine braking is good to limit speed on descents, but that's not how you stop when you really need to. Doing all of the braking for over 1000 lb of trailer is a big deal to a vehicle the size of a Wrangler. You'll only find out how big a deal if you really test it, which could be a fatal experiment.

As in the post, its an unlimited, which is 3,500 lb towing capacity.

I trust that the rating for the maximum total trailer weight is 3500 lb... but what I'm talking about is another, independent, limit on the weight of a trailer without brakes. For full-size pickup trucks (and SUV versions of the same vehicles) that limit is usually 2000 lb; for most other light vehicles (cars, minivans, small SUVs...) it is typically 1000 lb.

For example, a well-equipped "half ton" pickup can tow up to about 10,000 lb... but still needs trailer brakes for trailers over 2000 lb.
Another example: my Toyota van can tow 3500 lb... but needs trailer brakes if the trailer is over 1000 lb.

This limit normally shows up in the context of a statement in the towing section of the owner's manual... but I don't have a manual for a Wrangler Unlimited (or any Jeep) to check.

[brian_bp]

Okay, I found it in the Towing Guide - Checklist from Jeep:

If the trailer/load exceeds 1,000 pounds, the trailer should have its own brake system