There are self adjusting electric brakes for 10 & 12 inch setups... Just put a set if 10 inch on my car carrier (replaced original non auto adjust) ....May be only a matter of time till they are available for 7 inch....
http://www.etrailer.com/Trailer-Brakes/ ... 3-469.html
http://www.etrailer.com/Trailer-Brakes/ ... 3-468.html
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