Sundowner trailers: what wears first and what it costs

Sundowner Trailers, Inc. is based in Coleman, Oklahoma, and its owner’s manual covers horse trailers with and without living quarters. On a Sundowner, the owner’s manual itself points at what wears first: the floor under the mats, the drop ramp counterbalance, and the running gear. We are independent, not a Sundowner dealer or service center. Typical prices: aluminum floor work about $12 to $20 per square foot, ramp repair about $290, bearing repack $150 to $250 per axle.

What fails first on a Sundowner

• The floor. Sundowner’s manual is unusually blunt: “To prevent severe floor corrosion to this trailer: rubber mats should be removed every sixty days and trailer washed thoroughly.” That is the shortest mats-out interval of any maker we cover. See aluminum corrosion and white powder.
• The drop ramp. The manual says the weight of a drop ramp is partly held by a torsion spring and/or a cable, that you should stand to the side when opening it, that the cable should be inspected for fraying, and that the spring is not user serviceable. See ramp too heavy to lift.
• Breakaway. Sundowner says to check the breakaway system before each tow by pulling the pin and test towing at under 5 mph to feel the trailer resist, and that the breakaway is not a parking brake. See breakaway battery dead or not holding.
• Bearings. The manual says unsealed bearings must be inspected and lubricated once a year or every 12,000 miles, that a wheel bearing immersed in water must be replaced, and that a trailer unused for an extended time needs its bearings inspected and packed at least every six months and before use. Its living-quarters section adds: feel the hubs at fuel stops, and replace bearings that have overheated or grind. See hub hot or wheel noise.

Acid washing, the Sundowner way

Some owners acid-wash their aluminum trailers. Sundowner’s warning is specific: remove the rubber mats before acid-washing, and rinse the trailer thoroughly before the mats go back. If you do not, the warranty is void. Acid left under a mat is the floor corrosion problem made worse.

Typical Sundowner repair prices

Same ranges as any make; see the pricing page.

Living quarters

Some Sundowners carry living quarters, and the manual has a whole section for them. We work on the trailer: floor, frame, running gear, ramp, doors and the trailer’s own lights and brakes. The living-quarters plumbing, appliances and RV electrical need an RV shop.

Warranty first

If your Sundowner is under warranty, start with a Sundowner dealer. We do not handle warranty claims. For everything else, see horse trailer repair and trailer floor replacement.