How do I know what size wheel bearings I need for my trailer?

The easiest way to determine which bearings are used on your trailer axle is to take the hub off and check for the numbers stamped into the bearings. If the bearing numbers cannot be read, the next best solution is to find the bearings’ inner diameter.

You can measure the dimensions of a bearing by using a vernier caliper like the one below or measuring accurately with a ruler. All bearings will have an inner diameter (ID), an outside diameter (OD) and width (W). Bearings are sometimes referenced by these dimensions, in that order: ID x OD x W.

Likewise, are all trailer wheel bearings the same? With standard bearings, the inner bearing is larger than the outer, but with parallel bearings they’re the same size. For heavier-duty trailers there are 1.5 tonne, 2 tonne, 3 tonne sets.

Also, how do I know if my trailer wheel bearings are bad?

They should be listening for any squeaks, grinding noises, clicking or any other sound emanating from the trailer wheels. If noise is heard, check for a bad bearing or if lubrication is needed. Check for Heat – Tow the trailer for a short distance, 5-10 miles at highways speeds, then park the trailer.

How do I know my trailer axle size?

To find the load capacity for your axle you should look on the trailer VIN plate or sticker that lists the VIN number. The weight rating of the axle should be listed on that same plate or sticker. Also, the axle could have a tag or plate on it that will list the weight capacity.

How do I know what size trailer brakes I need?

To determine the size of the brake assemblies you need you have to measure the depth and width of the hub drum on the axle like what you see in the picture I attached. The most common size is 2-1/4 inch wide like the # T4071600-500 that you referenced.

How do I know what axle weight to use?

How to Calculate Axle Weight Add the total weight of the load you will be carrying to the total trailer weight. Divide the total weight of the load and trailer by the total number of tandem axles. Include the load bearing axle in your count. Write down the total weight of your tractor or pickup.

How do bearing buddies work?

How a Bearing Buddy Works. The axle hub is filled with grease until the grease forces the Bearing Buddy piston outward about 1/8 inch. Lubricant level (and pressure) can be checked quickly by pressing on the edge of the movable piston. If you can rock or move the piston, the hub is properly filled.

Are all trailer axles the same?

In almost all cases 3,500 lb axles will all use the same bearings. If your trailer has a Lippert or Dexter 3,500 lb axle then yeah they would be the same.

What is the difference between oversized and undersized bearings?

The outside diameter of the bearing is what fits into the engine block, and the crankshaft rests on the inside diameter. An oversized bearing has the same inside diameter but a bit more material on the outside diameter. An undersized bearing measures the same outside but is thicker on the inside.

What are parallel bearings?

The bearing on the outside is called the outer bearing. Parallel bearings are generally considered better for off road use as they have a higher load rating (1600 kg). With standard bearings, the inner bearing is larger than the outer, but with parallel bearings they’re the same size.

How long do trailer wheel bearings last?

approximately 85,000 to 100,000 miles

What causes trailer bearings to go bad?

A potential cause for bearing failure is the castle nuts being over tightened. Castle nuts should be just slightly more than hand tight. If too tight this will put excessive pressure on the bearings and could lead to premature failure. I suggest an inspection of the tires on the affected wheels.