My parents used to have a 21' travel trailer with brakes on only one axle. Like the other guys said, it's better than nothing, but having brakes on all axles is preferable. And of course, there are probably state laws in all states specifying what is required in the way of brakes. I don't know what is required in other states, but in Texas . .
</font><font color="blue" class="small">( § 547.401. BRAKES REQUIRED. (a) Except as provided by
Subsection (b), a motor vehicle, trailer, semitrailer, pole
trailer, or combination of those vehicles shall be equipped with
brakes that comply with this chapter.
(b) A trailer, semitrailer, or pole trailer is not required
to have brakes if:
(1) its gross weight is 4,500 pounds or less; or
(2) its gross weight is heavier than 4,500 pounds but
not heavier than 15,000 pounds, and it is drawn at a speed of not
more than 30 miles per hour.
Acts 1995, 74th Leg., ch. 165, § 1, eff. Sept. 1, 1995.
§ 547.402. OPERATION AND MAINTENANCE OF
BRAKES. (a) Required brakes shall operate on each wheel of a
vehicle except:
(1) special mobile equipment;
(2) a vehicle that is towed as a commodity when at
least one set of the towed vehicle's wheels is on the roadway, if
the combination of vehicles complies with the performance
requirements of this chapter; and
(3) a trailer, semitrailer, or pole trailer with a
gross weight heavier than 4,500 pounds but not heavier than 15,000
pounds drawn at a speed of more than 30 miles per hour, if the brakes
operate on both wheels of the rear axle.
(b) A truck or truck-tractor that has at least three axles
is not required to have brakes on the front wheels, but must have
brakes that:
(1) operate on the wheels of one steerable axle if the
vehicle is equipped with at least two steerable axles; and
(2) comply with the performance requirements of this
chapter.
(c) A trailer or semitrailer that has a gross weight of
15,000 pounds or less may use surge or inertia brake systems to
satisfy the requirements of Subsection (a).
(d) Brakes shall be maintained in good working order and
adjusted to operate on wheels on each side of the vehicle as equally
as practicable.
Acts 1995, 74th Leg., ch. 165, § 1, eff. Sept. 1, 1995.
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