3.5k Straight Axle Beam, 82.5" HF, 2.4" Tube, Straight, with Loose Perches
A 3,500 lb straight trailer axle beam kit with an 82.5" hub face, 2.4" axle tube, and two loose weld-on spring perches. Built for trailer and camper axle replacement work where the measurements and spring-center setup match.
Overview
This 3.5K straight axle beam kit is a replacement axle solution for trailers or campers that commonly use 5-lug hubs or 10" drum brake assemblies. The kit includes the axle beam and two loose SP-2375 spring perches for weld-on installation at the correct Spring Center measurement.
R&P Service Insight
Axle replacement is measurement-driven. Before ordering, confirm hub face, tube diameter, spindle/bearing setup, brake flange spacing, and Spring Center requirements.
- Hub Face First: This listing is for an 82.5" hub face axle beam.
- Loose Perches: The included perches are not welded by default and must be positioned to your trailer’s Spring Center.
- Camber Direction: This straight axle beam is cambered; the arch goes up in the middle when installed.
R&P Knowledge Hub
Compatibility: Common replacement axle for trailers or campers that typically have 64.5" to 70.5" floor deck width and use 5-lug hubs or 10" drums where dimensions match.
Axle Setup: 3,500 lb straight axle beam, 82.5" hub face, 2.4" tube, cambered beam, EZ Lube spindle style.
Installation Notes: Spring perches are included loose. They must be measured, squared, and welded before the axle is placed into service.
Performance Insight: A properly measured axle keeps the hubs, tires, suspension, and frame tracking correctly. Do not guess axle measurements from deck width alone.
Brand & Fitment Note
Selling Brand: R&P Carriages curated axle kit using a Lippert 3,500 lb bare axle beam and loose SP-2375 spring perches.
Application Reference: This axle is intended for trailer and camper replacement applications where hub face, tube size, brake flange spacing, bearing setup, and spring layout match the existing trailer.
What This Means: This listing is for an axle beam kit with loose spring perches. It does not include hubs, drums, bearings, seals, brake assemblies, U-bolts, or mounting hardware unless specifically listed in the included components table.
Before Ordering: Verify the axle dimensions, hub face, brake flange spacing, spring-center requirement, hub/drum style, bearing set, seal, and brake configuration before installation.
R&P Repair Insight
This is a bare axle beam kit, not a complete hub-and-brake axle assembly. Reusing old hubs or brakes may be possible only when the existing parts match the spindle, bearing, seal, and brake-flange setup.
- Check the Bearings: This axle uses standard L44649 outer / L68149 inner bearings and 10-19 seals; these are not included.
- Check the Brake Setup: Confirm that your 10" drum or brake setup matches before transferring parts over.
- Check the Perches: Loose perches must be welded at the correct Spring Center before the axle is installed or towed.
Features
3,500 lb Straight Axle Beam
Replacement axle beam for 3.5K trailer and camper applications where the listed dimensions match the trailer.
82.5" Hub Face
Built around an 82.5" hub face measurement for trailers requiring this specific axle width.
Standard 2.4" Tube
Uses a standard 2.4" axle tube and includes SP-2375 spring perches for weld-on placement.
Loose Perch -KIT Configuration
Perches are included loose so they can be welded to the correct Spring Center for the trailer.
Specifications
| Specification | Detail |
|---|---|
| Part Number | 3500-825-24-KIT |
| Axle Beam | Lippert 3,500 lb bare axle beam |
| Product Type | Straight trailer axle beam kit with loose weld-on spring perches |
| Hub Face | 82.5" |
| Tube Diameter | 2.4" |
| Brake Flange to Flange | 76.16" |
| Bearing Shoulder to Shoulder | 78.69" |
| Spindle End to End | 86.88" |
| Bearing / Seal Reference | Uses standard L44649 / L68149 bearings and 10-19 seals. Bearings and seals are not included. |
| Camber | Straight axle beam is cambered; install with the arch up in the center. |
Fitment / Application
| Category | Details |
|---|---|
| Vehicle / System | Trailer or camper leaf-spring axle applications |
| Primary Fit | 3,500 lb axle replacement where 82.5" hub face, 2.4" tube, and listed measurements match. |
| Common Use Range | Often used on trailers or campers with approximately 64.5" to 70.5" floor deck width and 5-lug hubs or 10" drums, when the actual axle dimensions match. |
| Notes | Spring perches are included loose and must be welded at the correct Spring Center before road use. Do not install or tow with loose spring perches. |
Included Components
| Quantity | Item |
|---|---|
| 1 | 3500-825-24-KIT / Lippert Trailer Axle 3500 lb Bare Beam, 82.5" Hub Face, 2.4" Tube, Straight EZ Lube, USA Made |
| 2 | SP-2375 Spring Perch for 2.4" Axle Beam — ships loose unless welding is requested, measured, and confirmed before shipment |
| Not Included | Hubs, drums, bearings, seals, brake assemblies, U-bolts, plates, nuts, and installation hardware unless separately purchased or specifically listed. |
What Comes in the -KIT: Spring Perches Are Included Loose
This -KIT includes the axle beam and loose spring perches / spring seats. The spring perches are included as separate pieces. Included does not mean welded.
Spring perches ship loose by default. They are not welded to the axle tube before shipment unless the customer specifically requests perch welding in the order notes, provides the correct Spring Center measurement, and R&P confirms the weld-on request before the axle ships.
Repetition matters: If the listing says “spring perches included,” that means loose spring perches are included with the kit. It does not mean the spring perches are already installed, welded, or ready for towing.
When Will R&P Weld the Spring Perches?
R&P may weld the spring perches before shipment only when the order clearly gives us the information needed to do it correctly.
- The customer must request welded spring perches in the order notes.
- The customer must provide the Spring Center measurement.
- R&P must confirm the weld-on request before shipment.
How to Find Your Spring Center Measurement
Spring Center is the distance from the center of one leaf spring to the center of the opposite leaf spring. This is the measurement used to locate where the spring perches need to be welded on the axle tube.
- Best method with old axle: Measure from the center of one existing spring perch / spring seat to the center of the opposite spring perch / spring seat.
- Best method from the trailer: Measure from the centerline of the left leaf spring pack to the centerline of the right leaf spring pack where the axle sits.
- Leaf spring center bolt method: Measure from the center of the center bolt / locating pin on one spring pack to the center of the center bolt / locating pin on the other spring pack.
- Do not measure outside-to-outside. Spring Center is a center-to-center measurement.
- Do not guess from deck width. Deck width can be helpful context, but it is not a substitute for the actual Spring Center measurement.
Axle Measurement Diagram
Use the axle measurement diagram below as a visual reference while confirming axle dimensions and installation details. Spring Center must still be measured center-to-center at the trailer’s leaf springs or existing spring perches.
Why Welding the Perches Matters
This image shows a real-world installation problem where loose spring perches were not welded before use and brake wiring was torn out. This is exactly why the axle must not be installed, towed, or placed into service while the spring perches are still loose.
Loose perches can allow the axle to move or rotate out of its intended installed position. That can damage brake wiring, brake components, suspension parts, tires, and the trailer. The perches must be properly welded before road use.
| Question | Answer |
|---|---|
| Are spring perches included in the -KIT? | Yes. The spring perches / spring seats are included as loose parts. |
| Are the spring perches welded on by default? | No. They ship loose by default. |
| Can R&P weld the perches before shipping? | Only if the customer requests it in the order notes, provides the correct Spring Center measurement, and R&P confirms the request before shipment. |
| What measurement is needed for welding? | Spring Center: center of one leaf spring / spring perch to the center of the opposite leaf spring / spring perch. |
| Can the axle be used with loose perches? | No. Do not install, tow, or place the axle in service until the perches are properly welded. |
| What can happen if perches are not welded? | Loose perches can allow the axle to move or rotate, which can damage brake wiring, brake parts, suspension components, tires, and the trailer. |
| Which way does camber face? | If the axle is cambered, the arch goes up in the middle when installed. |
Order Note Wording Customers Can Use
Customers who want R&P to weld the spring perches should put clear instructions in the order notes before checkout.
