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Square #84 Spindle for 3,500-lb Trailer Axles - 1-1/2" Wide

Square #84 Spindle for 3,500-lb Trailer Axles - 1-1/2" Wide

Item # TRU47FR
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Square #84 Spindle for 3,500-lb Trailer Axles - 1-1/2" Wide Square TRU47FR
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Replacement #84 spindle welds onto your 3,500-lb trailer axle. Works with L68149 inner bearing and L44649 outer bearing. Castle nut, washer, and cotter pin included. Lowest Prices for the best trailer spindles from TruRyde. Square #84 Spindle for 3,500-lb Trailer Axles - 1-1/2" Wide part number TRU47FR can be ordered online at etrailer.com or call 800-298-8924 for expert service.
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TruRyde Trailer Spindles - TRU47FR

  • For 3500 lb Axle
  • Standard Spindle
  • 1-1/2 Inch Diameter
  • Square
  • TruRyde

Replacement #84 spindle welds onto your 3,500-lb trailer axle. Works with L68149 inner bearing and L44649 outer bearing. Castle nut, washer, and cotter pin included.


  • Tapered spindle replaces a worn or damaged #84 spindle on your trailer
    • Can also be used to build a custom axle
  • Weld-on installation
  • Sturdy steel construction
  • Castle nut, washer, and cotter pin included


  • Application: 3,500-lb trailer axles
    • Spindle capacity: 1,750 lbs
  • Stub dimensions: 1-1/2" wide x 3-5/8" long
  • Overall spindle length: 8-1/4"

Bearing, Race, and Seal Information

  • Bearings (sold separately)
    • Inner bearing: L68149 (1.378" inner diameter)
    • Outer bearing: L44649 (1.063" inner diameter)
  • Races (sold separately)
    • Inner race: L68111
    • Outer race: L44610
  • Grease seal (sold separately): 58846
    • Inner diameter: 1.719"
    • Outer diameter: 2.565"

spindle diagram

Part NumberCapacityABCDEFRound/Square
TRU47FR1,750 lbs1.50"1.719"1.378"1.063"1.00"3.625"Square

SP-20484-SQNWC TruRyde (TRP) Replacement #84 Square Spindle for 3.5K Axles - 1.50" Wide x 8.25" OAL

Replaces SP20484


Ask the Experts about this TruRyde Trailer Spindles

  • Replacement Square Spindle for 1994 Trail Rite Trailer
    For your axle the spindle you need the Square #84 Spindle for 3,500-lb Trailer Axles - 1-1/2" Wide # TRU47FR. This does not have the attached brake flange so you will need to either modify a flange like # 4-35 or salvage the one you have.
    view full answer...
  • 84 Spindle with Brake Mounting Flange Recommendation
    Adding brake mounting flanges to a spindle is something that only a qualified welder with experience welding them on should do. A much easier solution would be to go with a spindle that has a flange mounted to it already like the part # TRU74FR that would fit the same hubs as the # TRU47FR that you referenced. Also, the # TRU47FR is a square spindle and we only offer flanges for round spindles.
    view full answer...
  • Recommended Hubs and Spindles for 2500 lb Homemade Trailer
    The first thing to determine is if you want an idler hub or a hub/drum. The weight threshold at which brakes are mandated varies by state, so you might want to check that with your state police or highway patrol. If you decide on an idler hub (no brakes), I'd recommend the # 42655UC1 hub from Dexter Axle. The bearings, races, grease seal, lug bolts and grease cap are included. The hub will have more than enough capacity for your application. This hub would use the # TRU57FR spindle. For...
    view full answer...
  • How to Determine if Trailer has 84 Spindle to Pick Out Replacement
    In order to verify the spindle dimensions so that you can pick out the correct hub/drum you have to get exact dimensions. For that you need to use a digital caliper like part # PTW80157. For how old your trailer is this is especially important as the standard spindles sizes have changed since 1969. An 84 spindle would measure 1.06 where the outer bearing rides, 1.38 where the inner bearing rides, and 1.73 where the seal rides. For a hub with a 6 on 5-1/2 inch bolt pattern that would...
    view full answer...
  • Spindle Recommendation for Trailer Hub with Bearing Dimensions of 1.25 and 1.75 inch
    The spindle you would need based on the dimensions you provided is what is referred to as a #42 spindle. The part # TRU37FR would fit and has a 5 bolt mounting flange for the brake assemblies. These have a 2,600 lb capacity per spindle. I attached a review video for you to check out as well as a picture that has all of the dimensions of the spindle listed.
    view full answer...
  • Where to Measure a Trailer Spindle for Replacement Bearings, Seals, and Hubs
    I have included a picture that shows where you will want to measure the spindle. Measurements need to be as accurate as possible so I recommend using dial or digital calipers to take the measurements. If the other hub is still present you could pull it and get the inner and outer bearing numbers from it.
    view full answer...
  • Recommended Hub Assembly For 1 Inch Diameter Spindles
    A BTR spindle uses a 1.063" diameter L44649 bearing and a BT8 spindle uses a 0.99" diameter L44643 bearing. In order to find out which you have you will need to pull the hub and either measure the spindle diameter where the inner and outer bearings ride with a digital caliper like # PTW80157 and/or look for the bearing numbers on stamped on the inside of each bearing. For a 1 inch in diameter spindle, I recommend the Trailer Idler Hub Assembly for 2,000-lb Axles - 4 on 4, # AKIHUB-440-2-1K....
    view full answer...
  • How to Determine Hub and Spindle Size
    The spindle dimensions are as follows: A is the mounting dimension, B is the seal dimension, C is the inner bearing surface, D is the outer bearing surface and E is the diameter of the threaded portion of the spindle for spindle nut selection. Say you need a spindle and hub for a wheel with 5 on 4-1/2 inch bolt pattern and an axle that is 3500 lbs. For a single axle trailer you can use two of either the item # TRU64FR, if your axle is round or item # TRU47FR if your axle is square....
    view full answer...
  • Tips for Determining Square Trailer Axle Capacity
    Square axles can be tough to determine capacity. Often times the same spindle fits a range of axle capacities. The best way to determine the capacity is to get the inner and outer bearing numbers stamped into the metal of the bearings like you did. The numbers you listed do not match any of the spindles we carry though so I was not able to determine anything from that. The bolt pattern of the hubs on the trailer is typically used on 2k-3.5k axles, most 15 inch wheel trailer setups have...
    view full answer...
  • Where to Measure on Trailer Spindles to Determine Replacement Hubs
    You will need to measure the diameter of the spindles where the seal and bearings ride. Check out the picture I attached that shows where this is. You will need an exact measurement so either a digital or dial caliper will be needed. To pick out the correct hubs you will also need to determine the bolt pattern of the hubs you currently have so that the new ones will be compatible with your current hubs. I attached an FAQ on how to determine this. If you get back to me with that information...
    view full answer...
  • Replacement Hub Assemblies for 2004 Tracker Trailstar Trailer
    If your hub uses the # L44649 bearing (1.063 inch inner diameter) for both the inner and outer bearings, and your Tracker Trailer is equipped with 2,000 pound axles, the correct hub and drum assembly should be the Dexter # 8-257-5UC3-EZ. For an idler assembly you can use part # 8-258-5UC1-EZ. These feature the 5 on 4-1/2 inch bolt pattern that you mentioned as well. I was not able to cross reference the seal number that you provided, so you will just want to make sure that your existing...
    view full answer...
  • Old Trailer has 2 Different Sized Spindles and Obsolete Bearing and Seal Numbers
    That looks like a mobile home axle. It is possible that both axles are mobile home axles. But the problem with that is they are meant for one time use only. People get them because after they are used they are cheap. It is possible that this is also why the axles have two different sets of bearings. It is also extremely difficult to find parts for mobile home axles. The 2788 and 1779 bearings are associated with hub 22834 which is not available. The seal sounds like a # 29031 which has...
    view full answer...
  • How to Accurately Measure Spindle Dimensions
    The range of trailer spindles we offer is shown on the linked page. These include both round and square stub types rated for axles ranging from 2,000 lbs to 7,000 lbs. On the chart you can see the key dimensions for five points on the spindle, including where the grease seal rides (B) and where the bearings ride (C and D). Spindle dimensions must be taken with precision, to the nearest few thousandths of an inch; fractional dimensions are not accurate enough so you will want to use a...
    view full answer...
  • Recommended Spindle And Hub Assemblies For 1-1/2 Inch Square 2,000-Lb Axle
    The spindle that you referenced, part # TRU47FR, will work great for you. This spindle features a 4 inch long stub, and is rated for a 3,500-lb axle. I have attached a link to a product review video for this spindle you can check out. The installation of this spindle should be done by a qualified professional welder because it is important that the spindle is welded in place as square and concentric as possible. The hub assembly designed to work well with the TRU47FR spindle is part...
    view full answer...
  • Weld-On Spindle for Trash Trailer Without Suspension
    If you don't need any suspension, then you can use a square pipe and the TruRyde Spindle # TRU47FR you referenced welded directly to the trailer. I don't recommend welding the spindle without more support to disperse weight as a bump could cause that spindle to break or bend without more support. I assume you will be using for light loads but it is probably worth mentioning that no suspension cuts a trailer's capacity in half so with the unknown capacity of your trailer you won't be...
    view full answer...
  • Removing and Replacing Trailer Spindles
    To replace a spindle, the old one would need to be cut off, and the new one welded into place. This is NOT a job for the do-it-yourselfer. The new spindle must be absolutely square with the axle in order to prevent premature tire wear and wheel tracking problems. I would recommend finding a welder who is experienced with trailer axles. Your local RV dealer or repair facility could probably refer you. In many cases, it's less expensive to simply replace the trailer axle itself. We offer...
    view full answer...
  • How to Tell if a Trailer Spindle is Damaged or Needs to be Replaced
    If you remove the hub and wipe away the grease on the spindle you can check to see if it is damaged. Look for an scarring, gouges, discoloration, or scoring on the spindle. If the spindle is damaged then the bearings won't ride properly and can fail again or it can cause other problems such as uneven or excessive tire wear and ride quality problems. If the spindle is damaged then you can't really repair it and the whole axle should be replaced. I doubt that this is the case based on...
    view full answer...
  • How to Pick Out Replacement Hubs for a Boat Trailer
    In order to pick out the correct hub assembly for a trailer you are going to need know a few key pieces of information. The first thing you will need to know is the bolt pattern of your hubs. Since the figure you came up with doesn't match any of the 5-bolt bolt patterns I am going to need to to recheck your bolt pattern. For further info on this check out the FAQ article I attached on this. Next thing you will need to know is what spindle you have on your trailer. In order to do that...
    view full answer...
  • How to Determine Capacity of Square Axle
    Square axle capacities are pretty hard to determine. Unlike round axles, they do not have set capacities based on their dimensions. Based on the bearings your hub looks like it's rated for 3,500 lbs. Most likely that would be the same rating as your axles.
    view full answer...
  • Determining the Capacity of a Square Trailer Axle
    Square axles can be tough to determine capacity. Often times the same spindle fits a range of axle capacities. The best way to determine the capacity is to get the inner and outer bearing numbers stamped into the metal of the bearings. Going by those numbers, wheel size, and bolt pattern, we can determine the probable axle capacity. I have included some links that might help. There could also be a plate on the axle itself that lists the capacity. The most common place to find axle capacity...
    view full answer...
  • Welding #84 Spindles # TRU84FR and # TRU57FR for Utility Trailer with 2-3/8 inch O.D. Pipe
    You have a 2-3/8 inch O.D. pipe so you might want to look at #84 Spindle, # TRU84FR, which has a 2 inch O.D. at the weld point and has a 1750 lb. capacity, so two spindles will give that axle 3,500 lb capacity. The #42 Spindle, TRU57FR which has a 2.25 inch O.D. at the weld point and is rated for 5,200 lbs to 7,000 lbs axles. The total capacities of the spindles are only valid if installed correctly and the axles are not broken or damaged in any way. The TruRyde #84 Spindle, # TRU47FR,...
    view full answer...
  • How to Pick Out Replacement Hub for a Trailer with Rusty Hub
    Your question came in blank, but it looks like you are looking for replacement hubs based on the pictures you submitted. In order to pick out the correct hub assembly for a trailer you are going to need know a few key pieces of information. The first thing you will need to know is the bolt pattern of your hubs. This is so you get a hub that is compatible with your wheels. I attached an FAQ article on determining bolt pattern for you to check out. Next thing you will need to know is...
    view full answer...
  • How to Identify Compatible Hubs for Vintage Utility Trailer
    Thank you for the photo of your vintage utility trailer's spindle. The simplest and surest way to identify a compatible trailer hub is to identify the inner and outer bearings and the grease seal it uses. Matching up those components along with the axle weight rating and the hub bolt pattern is pretty much it. However, in your case I can tell you up front that we have only one hub that uses a bearing whose inner diameter is as small as 0.75-inches, hub # AH15450ECOMP. It uses outer...
    view full answer...
  • Does a Spindle with Scarring and Complete Bearing Failure Need to be Replaced
    What concerns me about this situation is the scarring on the spindle. Depending on how deep and how bad the scarring is, a new set of bearings and a new hub/drum assembly might experience the same problem down the road. This would mean that the spindle would need to be replaced also. Otherwise, you may have to frequently replace parts. It would be best in this situation to eliminate the possibility of future similar occurrences before they have a chance to cause damage. Any visible scarring...
    view full answer...
  • Can 15 inch Trailer Wheels be Replaced with 14 inch Trailer Wheels
    To go from a 15 inch trailer wheel to a 14 inch trailer wheel would only require you to match up the bolt pattern of what you currently have with what you would like to install. You will first need to determine what bolt pattern you have on your wheel. I attached a link to a help article that details how to do this. In the 14 inch trailer wheel size we have only the 5 on 4-1/2 inch bolt pattern. This is a very common bolt pattern though. You have the choice of a 215/75-14 like...
    view full answer...

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Info for this part was:

Edited by:
Lindsey S
Installed by:
Kathleen M
Written by:
Alexander C

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