Dexter axel brake up grade

I've had popup and snowmobile trailers with 7" brakes for the past 38 years. I can tell you they have been nothing but useless junk. The biggest problem has been the magnets actually coming off the arm, now I braze the clips in place.

If you can come up with a way to fit 10" brakes it would be well worth the effort.

I think the biggest concern should be your ability to control speed by downshifting to a lower gear. At the time you had all of your brakes smoking, were you in a lower gear? You may need to be at a fairly high rpm to help control your speed, this is okay. This needs to be your primary method to control speed coming down a mountain grade. You will never be able to upgrade your brakes to the point where they can handle constant use coming down a mountain. This is true if you are towing or not.

If you were smoking the brakes, you were either going too fast, needed to use a lower gear, or your teardrop is over 3000 lbs, the limit for you Outback.

Regardless of what was the issue, you might look into upgrading the brakes rotors and pads on the Outback to the Legacy rotors (bigger) See this thread for some more ideas on making your Outback have better brakes.
http://www.subaruoutback.org/forums/65-parts-accessories-performance/20124-brake-upgrades.html

We had a problem coming down Tioga pass three years ago. Both the trailer brakes and TV brakes were smoking. One of the reasons I am interested because we are looking at at trip to Alaska and one individual with a teardrop just completed that trip and made the comment that their tear which is a couple of hundred pounds less than ours had one brake fail. They did not have a problem becuae the TV was a pickup.
The axle is a Dexter torsion bar and with the weigh of the trailer you might as well not have any spring at all with a heavier duty axle. If I have to switch I will probably move to a Flexride axle.

You would probably have to buy a new heavier duty axle to get the larger brakes. Of course then you might need new springs and such. Do you have a problem with the existing brakes not being strong enough, or do you you just want to change them out for peace of mind?

Replace the axle to upgrade brake size.. I did it from Dexter 7000k 12x 2s to 8000k 2 1/4 x 3 3/8 forward self adjusting brakes under our 5er.
Much better braking and tire wear.
I had a use for the old 7 k axles, to build a hydrauilic dump bed trailer. You can find a buyer or use for yours
Look at rednecktrailersupply.com or statetrailer.com