Most applies to RV's....from Shorlander trailer, and yes over 10 years old. I inserted bold font of areas of concern that make me think before going oil bath.
IDA GROVE, Iowa 4/22/05— As this year's boating season approaches there is a new debate among boat owners about the best way to maintain their trailers. The debate centers around grease pack versus oil bath hubs. ShoreLand'r, a leading manufacturer of boat trailers, offers a note of caution to owners thinking of switching to oil bath hubs or purchasing trailers with that type of hub.
ShoreLand'r uses grease pack hubs exclusively because they offer the majority of boat owners the most protection, reliability and convenience. Oil bath hubs have been used for years on large over the road trucks and trailers. America's highways offer the perfect environment and application as the constant miles and tire rotation keeps the bearings well lubricated. Also, with minimal down time there is little opportunity for condensation to form inside the hubs.
Boat trailers, however, operate in a completely different environment. The hubs on a trailer can heat up during long trips and when they are dipped into cool lake water, the sudden temperature change creates a vacuum inside the hub. This vacuum will draw any condensation, moisture or impurities directly into the bearing, which can cause premature bearing failure.
"For convenience and worry-free operation, grease packed hubs are better suited for the average boater," says Butch Williams, ShoreLand'r Sales Representative. "Grease packed hubs can be safely run for many miles even if the protector is knocked completely off the hub."
For the average boater using oil bath hubs, condensation also becomes a problem when the boat is stored over the winter, or only used a few times a year. With many oil bath hubs, it is necessary to rotate the wheels every other week to prevent rusting and pitting of the bearing surfaces when the boat is in storage. That is a chore that most boaters easily forget or ignore.
"Oil bath hubs may make sense in some applications, but when it comes to boat trailering, they are a disaster waiting to happen," says Tom Long, a licensed captain and outdoor writer from Jacksonville, Fla., who has seen every kind of trailer problem in his 40 years of boating.
"I've seen every trailer failure known to man and oil hubs tend to fail more often than grease hubs. From problems with condensation to constant maintenance, they just don't make sense for the average boater," says Long
Oil bath hubs should be checked after every loading/unloading cycle to make sure water has not penetrated and diluted the oil. Small leaks can cause the oil to escape and once this happens, bearing failure is quick and complete within a few miles. Most oil bath hubs are only half filled with oil and must be carefully inspected to maintain the proper level. Too much or too little oil could cause problems.
By comparison, standard bearing protectors make it easy to visually check the amount of grease inside grease packed hubs. The internal spring piston exerts about 3 p.s.i. against the grease to ensure that no water enters the hub when the hub is submerged during loading and unloading. When properly maintained there are no voids inside the hub where condensation can form during winter storage.
Jim Pritchard, owner of Fat Cat Trailer Repair in Jacksonville, Fla., agrees that when an oil bath hub fails it can get expensive in a hurry, "Not only are oil bath hubs more expensive to replace in the event of a failure, an owner might be faced with an expensive towing bill to the nearest marine dealership. In addition to replacing the hub and bearings, the axle might have to be replaced as well. By comparison, a bearing protector would cost around $20 to replace and the likelihood of damage to the axle is small.
"We see a higher failure rate of oil bath hubs, especially with boat trailers," says Pritchard. "If it was my trailer, I'd go with the grease packed hubs every time. They are the only way to go for greater reliability and peace of mind."
ShoreLand'r recommends the use of grease-packed hub for greater dependability and reliability. Oil bath hubs require constant maintenance to ensure that the oil level is properly filled. The presence of air inside the hub can allows condensation to form, and rust to develop on the bearings.
