As spring wades into summer, boaters turn their thoughts to vacation travel, to hitching up their trailers to SUVs and heading for the open road. Or perhaps they're buying a boat and trailer for that all-important dream trip south to the Florida Keys or maybe north to Cape Cod.

Since the enormous majority of boats registered in the United States fall below the 26-foot mark, according to the National Marine Manufacturers Association, that means thousands of you may be trailering in the next few months. Before you venture out, consider not only your boat and its integrity, but also your trailer. Do you have the optimum setup for your small boat?

To help steer you in the right direction, we asked trailering experts and anglers who log lots of road-weary hours heading to hot spots or fishing in inshore tournaments.

The 20/4,000 Debate
My first question to trailer experts created a controversy. But what could possibly be controversial about trailers?

OK, you try answering this: For what size or weight vessel should one transition from a single-axle to a tandem-axle trailer? 20 feet? 23 feet? 3,000 pounds? 4,000 pounds?

"The general rule goes like this," says Pat Piper, editor of Trailering magazine, a publication of the BoatU.S. Trailering Club. "If the boat is less than 20 feet long, a single axle is fine. If it's 20 feet or longer, you're in dual-axle territory.

"When a boat is longer than 20 feet, a lot of weight is being placed on a single axle — especially when on the highway at a high speed and hitting a bump or going around a curve."

However, Mike Melone at ShorLand'r, an Iowa company that builds boat trailers, says in-house engineers build to a 4,000-pound cutoff. ShorLand'r believes the weight of the boat should determine the style of trailer. 

Other trailer manufacturers use a 21-foot figure; some say 23 feet or 3,000 to 3,500 pounds.

When you're buying a boat, the dealer will usually match it to a trailer. However, if you already have a boat or want more information than what your dealer provides, visit trailer-company websites. Many offer matchups based on size and weight for their specific trailer designs.

ShorLand'r, for instance, builds its aluminum trailers with galvanized-steel crossmembers, which add strength to support slightly heavier loads. Other trailer makers build all-aluminum designs.

Of course, aluminum weighs less and offers better corrosion protection than galvanized steel, an important   factor for saltwater anglers. However, many Pacific Northwest boaters choose the heavier-duty steel. In the end, proper maintenance becomes key for any boat trailer used in salt water.

Bunks vs. Rollers
If your boat remains on the trailer most of the time, you may prefer a trailer with bunks: carpet-covered wood beams that distribute the boat's weight over a greater area. However, rollers can also offer good support, especially if you increase the  number of rollers on which your boat rides.

"When I purchase a new boat trailer, I custom-order a double set of rollers on the trailer for my 18 1/2-foot boat," says Tom Migdalski, a Connecticut-based freelance outdoor writer and frequent contributor to Sport Fishing. "Instead of 16 rollers, mine has 32, which is the same number used for larger trailers. Although this costs more, it doubles the hull support, which will prevent long-term hull damage from sitting on the trailer and riding over rough roads."

Migdalski also purchased a trailer with a one-size-greater weight rating than he needed for his Maritime Skiff. "My boat weighs about 1,500 pounds loaded, and the trailer is rated for 2,200 pounds. I feel this covers a safety margin and adds to the longevity of the trailer."

His last Load Rite trailer, a galvanized-steel version, lasted for 14 years of twice-weekly 30-mile round trips during the fishing season.

Migdalski chose the roller style because the boat moves more easily onto and off the trailer and he can move the boat on the trailer by himself when he needs to wax the hull or replace parts.

"Roller trailers offer easier loading, particularly at lower-incline ramps," Melone says. "Bunk trailers are very popular down South and offer easier loading on very steep ramps."

Bearings and Brakes
The fact that a trailer's axle assembly submerges in salt water virtually every time an angler launches a boat emphasizes the critical nature of components such as bearings and brakes. According to BoatU.S., bearing failures ranked second among reasons for trailer breakdown in 2004. (Tire failures topped the list.)

"Bearings should be removed, inspected and repacked with high-grade grease annually," Migdalski says.

Grease-lubed hubs represent the longtime standard in the industry. However, oil lubrication has begun to gain supporters.

"The bearing is lubricated more often and faster with oil," says Piper. "As a trailer builds up speed, centrifugal force pushes the oil against the outside of the hub to bathe bearings in oil. With each revolution, the bearings are lubed four times."

Greased bearings suspend in the thicker lubricant and may not move as freely. When trailering long distances, inspect bearings at every fuel fill-up. Look for leaking grease or oil, hub heat buildup, smoking or wheel noise.

Many states now require separate trailer brakes on loads weighing more than 3,000 pounds; in some cases, those minimum weights may be 1,500 or 2,500 pounds. Remember, that's the weight of a trailer plus a fully loaded boat with engine. Many boats in the 18- to 24-foot range surpass those minimums.

To check your own state's laws and the regulations in states where you'll be traveling, visit www.boatus.com/trailerclub/laws.asp