Spindle 1.5" SQ x 4" STUB (1750 lb)

Spindle 1.5" SQ x 4" STUB (1750 lb)

Item # SP20484

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Shipping Weight: 4 lbs

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Spindle 1.5 Inch SQ X 4 Inch Long Stub
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Product Images


  • For 3500 lb Axle
  • Standard Spindle
  • Square
  • 1-1/2 Inch Diameter
  • 4 Inch Long
  • Redline
Lowest Prices for the best trailer spindles from Redline. Spindle 1.5" SQ x 4" STUB (1750 lb) part number SP20484 can be ordered online at etrailer.com or call 800-298-8924 for expert service.

  • All Info
  • Reviews (16)
  • Q & A (76)
  • Videos (1)
  • Photos
  • Why etrailer?

Redline Trailer Spindles - SP20484

  • Includes washer, castle nut and pin
  • Works with hubs that have L44649 and L68149 bearings

Part No. Capacity A B C D E F Round/Square
SP20484 1750 lb 1.50 1.73 1.38 1.06 1.00 4.00 Square

SP20484 Spindle 1.5" SQ x 4" STUB (1750 lb)

Video of Spindle 1.5" SQ x 4" STUB (1750 lb)

Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.

Video Transcript for Redline Trailer Spindles - Standard Spindle - SP20484 Review

Customer Reviews

Spindle 1.5" SQ x 4" STUB (1750 lb) - SP20484

Average Customer Rating:  4.6 out of 5 stars   (16 Customer Reviews)

- SP20484


I am building a custom trailer and these stub axles fit the bill exactly. Loved the personal service and the help. I tried a few other sources before going online to order from etrailer. [An online tool retailer] was one and their online site was a mess without help and so was a retail location. etrailer, was quick to find me exactly what I needed and got me fixed up in just a few minutes. From now on all my trailer needs will be fulfilled from etrailer!!! 466158

- SP20484


good quality, shipped in good protected wrapping, I use these in an unconventional way I install on side of trailer and mount complete hub assembly, with spare tire, if loose bearing or hub or lug nuts, I have everything needed to repair, plus spare tire. 297923

- SP20484


Product was received on time and was just what we needed. We had to get our trailer back into service quickly and the spindle we required was shipped out fast, and we were able to install it in our shop and get back to work. Thanks for a good product and great service. 558649

- SP20484


waited a few weeks for a few items, but was updated several times while I waited. the components all look great, good workmanship and such. only have a few miles on the set. will give a update after we have put some miles on them. thank you 468205

- SP20484


Thanks & fast shipping and nice perfect fit 1 1/2 square tube to 2" square tube 1/4 thick ! Thanks John Sliva 430570

- SP20484


I received my order on time, the package was a little beat up from the weight of 4 hubs and 4 spindles. They maybe could of used a little better protection inside the box as they were a little rough when I opened them, but they will still work fine. 341381

- SP20484


They worked very well 309860

- SP20484


Package was on the doorstep last night when I got home from work...very impressive service, tech support, and delivery time, thank you! 294598

- SP20484



- SP20484


etrailer always provides easy ordering options as well as fast order processing and delivery. Thanks, very happy. 211946

- SP20484


Product arrived as promised Parts look excellent Look to be correct for my application Now to see if they hold up Which I feel they will Thanks 184716

- SP20484


Your products and service are first cla ss. 173402

- SP20484


The axel stubs are very nice quality and will be easy to weld to my 2 X 2 Box Tube axel. I have had very good support from ETrailer for my home built trailer project. Thanks 129410

- SP20484


Timely and good 128963

- SP20484


Just what I was looking for. 122292

- SP20484


havnt used them yet but they look damn good :p 107380


Ask the Experts about this Redline Trailer Spindles
Do you have a question about this Trailer Spindle?

  • 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 # R20484, if your axle is round or item # SP20484 if your axle is square....
    view full answer...

  • Axle Kit for Fabricated Ice House Trailer
  • All of our trailer spindles are shown on the linked page, but none of these has a stub end to fit 2 x 3-inch tubing. All are either round like # R20384EZ or square like # SP20484. For a fabrication project like yours a better solution may be a bolt-on axle-less suspension kit from Timbren, such as # A12RS440, which is rated for 1200-lbs and which includes idler hubs with the 4-on-4-inch bolt pattern. Bearings, races and seals are included with hub. All Timbren axle-less kits and beam...
    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...

  • 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...

  • 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...

  • What Size Axle Does a #84 Spindle Fit
  • A true 1 inch spindle is a BT8 spindle. The next closest one would be the BTR spindle which is commonly referred to as a 1-1/16 inch spindle and is more common than the BT8. Both of these are typically used with 2,000 lb axles. A #84 spindle is bigger and is used for 3,500 lb axles. Common sizes for these are 2-3/8 inch round axle, 3 inch round axle, and 2 inch square axle. I have attached a helpful article that shows the different spindle selections that we offer and what size axles...
    view full answer...

  • Welding Redline Spindles # R40484 and # R50642 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 Redline Spindle 2 inch x 4 inch Round Stub, # R40484, which has a 2 inch O.D. at the weld point and has a 1750 lb. capacity, so two spindles will give that axle 3500 lb capacity or Redline Spindle 2-1/4 inch RD x 6 inch STUB, # R50642, which has a 2.25 inch O.D. at the weld point and has a 2500 lb. capacity for a total capacity of 5000 lbs. The total capacities of the spindles are only valid if installed correctly and the 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...

  • Parts Need to Build Off Road Trailer
  • Square axles can be tough to determine capacity, however the set up you reference above should be more than adequate for a towing weight of 1750 pounds. The Redline Spindle for Square Axles # SP20484, which you referenced, is a square spindle designed for 2 inch square axles and has a weight capacity of 1750 lbs, so it will work great for you. This spindle, # SP20484, is indeed compatible with Trailer Hub Assembly # 84655UC1, which you referenced. The hub assembly comes with the bearings,...
    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...

  • Spindle Recommendation for a Square 2x2 Axle
  • For your 2 inch by 2 inch axles you would want a Redline Spindle for Square Axles # SP20484. This is a square spindle designed for 2 inch square axles so it should work for well for you. Check out the review video I attached. The EZ Lube Spindle # R20384EZ you referenced is designed for round axles so it would not work for you. Spindles should be welded on by a qualified welder.
    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 # R50642 spindle. For...
    view full answer...

Do you have a question about this Trailer Spindle?

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Info for this part was:

Expert Research:
Michael L
Expert Research:
Robert G
Expert Research:
Michael H
Expert Research:
Jeff D
Expert Research:
Jameson C
Expert Research:
John H
Expert Research:
Adam R
Expert Research:
Rachael H
Expert Research:
Jeffrey L
Photos by:
Zach O
Updated by:
Sarah W

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