Aaron Williams, who provides tech support for Standard Bearings, offers answers to common questions about bearings in ag equipment:

OEM bearings tend to be better, but aren’t necessarily the best.

The original equipment manufacturer’s recommended bearing is generally the best combination of economy and durability for a particular application. But if there are concerns that a bearing isn’t durable enough, it’s possible to substitute a higher quality bearing. “You can use the part number off the old bearing and have Standard Bearings or another industrial bearing retailer upgrade it to a better-quality bearing,” says Williams.

Not all same-sized bearings are created equal.

Each manufacturer has its own quality specifications. “Timken is known to have higher quality parameters than some other bearing manufacturers,” says Williams. “Some of the Japanese bearings, like NSK and NTN, are good too. Price generally reflects quality.”

Grease affects bearing performance.

Avoid mixing different types of greases in a bearing. “Mixing a clay-based grease with a polyurea or moly grease could cause problems,” says Williams. “The different greases may not be compatible and create a situation that shortens bearing life.”

Over-greasing can cause bearing failure.

“Excess grease churns and creates heat,” he says. “The grease-interval recommended in the owner’s manual keeps enough grease in the bearing for lubrication without filling it so full it overheats. Overgreasing can also push out the seals, which obviously creates problems.”

Lock collars are simpler than you think.

“All you have to do is tighten a lock collar hand-tight, nice and snug,” says Williams. “No more than a tap, if you use a hammer and punch. Beating it tight can tighten a lock collar so tight that it will actually crack the eccentric lip on the inner bearing race or the lock collar itself.”

Clock-wise or counter-clock-wise?

“It’s best to lock a collar in the direction the shaft will turn, so centrifugal force helps keep it tight,” he says. “But it should hold just as well if it’s locked securely in the opposite direction.”