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. Aside from the actual part number, the inner diameter of a bearing is the best place to start identifying the bearing.
For axles in the 1,000 - 2,000 pound capacity, there are two common bearing combinations. Depending on the spindle that was used, your hubs and axle could require two L44643 bearings or two L44649 bearings. There is only about 1/16 of an inch difference in the spindle diameter that these two bearings fit, so it is important to make sure you choose the correct replacement bearings.There are two ways to do this:1) Look for the bearing number on the bearing itself.2) Use a caliper to measure the diameter of the spindle where the bearings ride. A spindle that uses bearings L44643 will measure 0.99 inches and a spindle that uses L44649 will measure 1.06 inches. We do not recommend trying to use a tape measure or ruler because there is only a fraction of a difference between these two diameters.
*Note: An alternative to using a grease cap is to use a bearing protector, such as those made by Bearing Buddy or Kodiak. A bearing protector makes it easier to grease the bearings on a standard trailer axle by featuring a grease zerk and works similarly to EZ Lube axles. Keep in mind that these are not designed for use on axles with EZ Lube fittings. For a set of Bearing Buddy bearing protectors that have a 1.98 inch outer diameter, you will want #BB1980A. For a bearing protector from Kodiak that offers a 1.98 inch inner diameter, you will want the Red Eye #KREB1980AC.2,300 - 3,500 Pound AxlesFor 2,300 - 3,500 pound axles, it is much easier to identify this size axle by its inner and outer bearing numbers. The most common bearings used on this size axle are the L68149 for the inner bearing and L44649 for the outer bearing.
For the L68149 bearing, the L68111 race is commonly used. It is important to note, however, many boat trailer manufacturers use this bearing with a L68110 race, which has a larger outer diameter of 2.327 inches. Checking for the part number stamped into the side of the race or measuring the outer diameter will help determine which race your axle uses.
*Note: If you have a standard axle you can upgrade the grease cap to a set of bearing protectors, such as Bearing Buddies or Kodiak's Red Eye. Bearing protectors feature a grease zerk fitting that makes it much easier to grease your standard axle's bearings. Keep in mind that these are not designed for use on axles with EZ Lube fittings. For Bearing Buddy, you'll want #BB1980A. For Kodiak, you'll want #KREB1980AC.
4,000 - 4,400 Pound AxlesWhile 4,400 pound axles are much less common than 3,500 pound or 5,200 pound axles, they are available. These axles also only use one common bearing combination for the inner and outer bearings. For the inner bearing, a 4,400 pound axle will use L68149 and for the outer bearing it will use LM67048.
*Note: To make it easier to grease a standard trailer axle's bearings, a bearing protector is a great solution. Keep in mind that these are not designed for use on axles with EZ Lube fittings. For a bearing protector set, you will want the Bearing Buddy #BB2441.
5,200 - 7,000 Pound AxlesAxles with capacities from 5,200 pounds to 7,000 pounds are commonly used on larger trailer that have tandem axle or triple axle setups. These axles all measure 3 inches in diameter, which is why they can easily be mistaken for each other. The part that differentiates axles in this range from each other is the outer bearing. The outer bearing is different in 5,200 pound, 6,000 pound, and 7,000 pound axles and determines which hub each size axle requires. When looking at axles in this weight range, it is important to know the axle capacity and the outer bearing number to ensure the components are the right ones for your axle.
5,200 Pound Axles
Getting into larger axle capacities, the identifying bearing will be the outer bearing. A 5,200 pound axle will use a 25580 inner bearing and an LM67048 outer bearing.
To choose the correct bearing kit for a 5,200 pound axle, it is important to know which grease seal your axle and hub require. The correct kit for a 5,200 pound axle is determined by the Inner Diameter needed for the grease seal. The spindle used will either require a 2.250 inch inner diameter grease seal or a 2.125 inner diameter grease seal. To determine which seal is the one needed for your trailer, you will want to use a digital caliper and measure the grease seal seat. If the diameter of the spindle is slightly over 2.25 inches you will need the kit that includes the 2.25 inch inner diameter seal, and if it is slightly over 2.125 inches then you will need the kit with the 2.125 inch inner diameter seal.
*Note: For a bearing protector, you can use the Bearing Buddy bearing protectors #BB2441. These fit a 2.441 inch hub bore and work with the LM67048 outer bearing. Keep in mind that bearing protectors are not designed for use on axles with EZ Lube fittings.6,000 Pound Axles
The inner bearing for a 6,000 pound axle is the same as that for a 5,200 pound axle, the 25580 bearing. For the outer bearing on this size axle, the most commonly used size is 15123.
Additional ComponentsThe grease seal needed for your axle will determine the correct bearing kit for your 6,000 pound axle, same as the 5,200 pound axles. The two different size seals are the same for this size axle. It will either require a 2.25 inch inner diameter seal or a 2.125 inch inner diameter seal.
*Note: If you want to upgrade to a set of bearing protectors, you will want Bearing Buddy #BB2441. These fit a 2.441 inch hub bore and work with the 15123 outer bearing. Keep in mind that bearing protectors are not designed for use on axles with EZ Lube fittings.
7,000 Pound AxlesFor 7,000 pound axles, the inner bearing used is again the 25580 bearing. The most commonly used outer bearing for this size axle is 14125A.
Additional ComponentsAs with 5,200 pound and 6,000 pound axles, 7,000 pound axles will use one of two different grease seals, either with a 2.250 inch inner diameter or 2.125 inch inner diameter, and this information is needed to choose the correct bearing kit.
*Note: For a set of Bearing Buddy protectors, you can use #BB2717, which fits a hub bore of 2.717 inches and work with the 14125A outer bearing. Keep in mind that bearing protectors are not designed for use on axles with EZ Lube fittings.
Dexter Nev-R-Lube Bearings
For some of their hub and drum assemblies, Dexter used an alternative bearing style to traditional tapered roller bearings. The Nev-R-Lube hub and drums are specifically designed to work with Nev-R-Lube bearings. These self-contained bearings come pre-lubricated from the factory and do not need to be re-greased like regular bearings. Nev-R-Lube bearing assemblies are shaped and designed differently than typical bearings, so the two are not interchangeable. Additionally, Nev-R-Lube hub and drum assemblies cannot replace standard hub and drum assemblies.
These bearings are available in 3 sizes. The size is determined by the inner diameter of the bearing assembly in millimeters. The 35mm bearing fits the 3,500 pound Nev-R-Lube hubs, the 42mm bearing fits their 5,000 - 6,000 pound Nev-R-Lube hubs, and the 50mm bearing fits their 7,000 - 8,000 pound Nev-R-Lube hubs.
Don't Know Your Axle's Capacity?
If you don't know your trailer's axle capacity, there are a couple ways to find out. The easiest way is to look for a plate or sticker somewhere on the axle that provides information such as the part number, lengths, and axle capacity.
If this label is long gone, another indication is the size of the axle tube.
Typical Axle Capacity
Measuring for Bearing Size
To be sure you find the correct wheel bearings for your axle, you will want to use a digital caliper to measure the spindle at the bearing seats. This will tell us the inner diameter of the bearings to determine which bearings are used on the spindle. If possible, it is best to measure the spindle out to 3 decimal places to allow for as specific of a measurement as possible.
Measuring both the inner and outer bearing seats on the spindle as well as the spring seat guarantees that we find the correct kit for the trailer axle. This bearing and seal seat information along with the diameter of the axle beam work together to confirm the capacity of the axle.
Updated By: Jacob JLast Updated On: 11/17/2023
Jb
8/6/2024
Thank you for this article and extremely helpful information! I have been on a wild goose chase for a few days before stumbling across this article which answered every question I had so I could properly inspect and re-pack the bearings on my 2004 R28BHS travel trailer.
Trailer wheel bearings are specific to the spindle that is installed on the axle that is on your trailer. You will need to safely support the trailer, remove the wheel and tire, remove the grease cap, remove the cotter pin and washer that secures…
To determine the correct inner and outer bearing, race and grease seal needed, you will need to take some accurate measurements from the spindle. If you will look at the diagram of the spindle on the right, we will need the B, C and D dimensions.…
It's not common for the spindle number to be printed anywhere on the axle. That said, if you're looking for new bearings/races and seals all you need to do is note the capacity or measure. The easiest method would be to crawl under…
Even though I cannot comment specifically on the grease you used because I am not familiar with it, I can tell you the best grease for trailer bearings is a a grease with a rating of GC-LB, which just means it is made to withstand very high…
We have 3 possible leaf springs lengths for your 2021 Keystone Passport Grand Touring Travel Trailer - you'll need to lift the trailer by the frame and measure from center eye to center eye to get the correct replacement. Here are the options we…
Hey Gary, so the holes that are on the CE Smith trailer axle part #CES84XR are currently at 38-1/2 inch on center so there would easily be enough room to put new ones at just 3/4 of an inch past where they are now but you would need to rotate the…
The ALKO 4,400 lb axles use the same bearing sizes as the standard 3,500 lb alxes. If you want USA made bearings, I recommend the Bearing Kit #TMK52VR. This kit comes with the Timken brand bearings which are all made here in the USA.
In order to determine the torque rating for the lug nuts on your trailer you will need to know check out the chart I attached that shows all of the torque specs for all the trailer lugs available based on stud size, wheel material and wheel size.
I certainly understand your reason for wanting to change them and it is possible to replace your drum hubs with idler hubs. Normally, it is recommended that if you have brakes on your trailer then you should keep them for safer towing. To make the…
We offer RV hub bearings and grease seals in many sizes; all such parts are shown on the linked page. These are available in single-lip, double-lip and oil bath types. We usually recommend using double-lip seals whenever available since they will do…
To determine the size of the hub assembly you need to purchase you have to determine which bearings are in the old assembly. If the old assembly has L44649 inner bearings, you would use the hub you chose #8-258-5UC1. If the inner bearings are marked…
Jb
8/6/2024
Thank you for this article and extremely helpful information! I have been on a wild goose chase for a few days before stumbling across this article which answered every question I had so I could properly inspect and re-pack the bearings on my 2004 R28BHS travel trailer.