Dexter 8,000 lb Trailer Axle Beam – 86.5" Hub Face – 3.5" Tube – EZ Lube – 4-Bolt Brake Flange
Heavy-duty Dexter 8K axle beam with 86.5" hub face, 3.5" tube, EZ Lube spindle configuration, and loose SS-350 spring perches included for final spring-center setup.
Overview
This Dexter 8,000 lb trailer axle beam is built for heavy-duty trailer running gear applications where an 86.5" hub face, 3.5" axle tube, 4-bolt brake flange, and TRUE 8K component match are required. It is intended for use with compatible 12.25" x 3.375" brake systems and matching Dexter 8-285 style hub/drum assemblies where all measurements and components match the trailer.
R&P Service Insight
An 8K axle beam must be matched carefully. Hub face, spring center, brake size, bearing set, seal size, and flange pattern all matter before installation.
- Hub Face: This axle uses an 86.5" hub-face measurement. Verify against the old axle before ordering.
- Spring Perches: SS-350 spring perches are included loose and must be welded at the correct spring center before road use.
- Brake Match: Designed around TRUE 8K running gear using 12.25" x 3.375" brake assemblies and compatible hub/drum components.
R&P Knowledge Hub
Compatibility: TRUE 8K Dexter axle configuration for compatible 8,000 lb trailer running gear setups.
Vehicle / System Fit: Trailer axle beam for heavy-duty trailers requiring 86.5" hub face, 3.5" tube, EZ Lube spindle setup, and 4-bolt brake flange configuration.
Installation Notes: Always verify hub face, brake flange-to-flange, bearing shoulder-to-shoulder, spindle end-to-end, spring center, bearing set, seal size, and brake/hub compatibility before installation.
Performance Insight: A TRUE 8K axle setup must stay matched as a system. Confirm brake assemblies, drums, bearings, seals, wheels, tires, suspension, and trailer frame requirements before placing the axle into service.
Brand & Fitment Note
Selling Brand: R&P Carriages / Need A Trailer Part
Application Reference: Dexter and 8K references describe the axle configuration, component family, and fitment target where supported by verified measurements and compatible running gear.
What This Means: This listing is for one Dexter 8,000 lb trailer axle beam with loose spring perches included. Required brake assemblies, hub/drums, bearings, seals, wheels, tires, U-bolts, and mounting hardware are not included unless specifically listed.
Before Ordering: Verify all axle measurements, spring center, brake size, flange pattern, bearing set, seal size, hub/drum requirements, and included components before installation.
R&P Repair Insight
When replacing a trailer axle beam, do not rely on capacity alone. Two 8K axle beams can look similar but use different hub-face dimensions, spindle layouts, brake/hub combinations, spring centers, and seal requirements.
- Confirm The Old Axle: Measure hub face, spring center, brake flange-to-flange, bearing shoulder-to-shoulder, and spindle end-to-end whenever possible.
- Check The Running Gear: Match the axle to compatible 12.25" x 3.375" brakes, Dexter 8-285 style drums, 25580 inner bearings, 02475 outer bearings, and the correct seal setup.
- Install Camber Correctly: If the axle is cambered, the arch faces up in the middle when installed under the trailer.
Features
TRUE 8K Dexter Configuration
Built for heavy-duty 8,000 lb trailer axle applications where a TRUE 8K Dexter running gear match is required.
86.5" Hub Face Measurement
Designed for trailer setups requiring an 86.5" hub-face axle beam. Always compare this measurement to the original axle.
3.5" Heavy-Duty Axle Tube
The 3.5" axle tube supports the larger 8K beam configuration and must be paired with compatible spring seats and suspension hardware.
Loose SS-350 Spring Perches Included
Two SS-350 spring perches are included loose for final spring-center placement and welding before the axle is used.
Specifications
| Specification | Detail |
|---|---|
| Part Number | 8000-865-35-KIT |
| Brand / Configuration | Dexter TRUE 8K axle configuration |
| Product Type | Trailer axle beam |
| Capacity | 8,000 lb axle class |
| Hub Face | 86.5" |
| Brake Flange to Flange | 77.41" |
| Bearing Shoulder to Shoulder | 83.625" |
| Spindle End to End | 92.375" |
| Tube Diameter | 3.5" |
| Brake Flange | 4-bolt brake flange |
| Bearing Set | 25580 inner / 02475 outer |
| Seal Size | 2.25" typical; some older trailers may use 2.125" |
| Brake Size Compatibility | 12.25" x 3.375" |
| Hub / Drum Compatibility | Dexter 8-285 style hub/drum assemblies where specifications match |
Fitment / Application
| Category | Details |
|---|---|
| Vehicle / System | Heavy-duty trailer running gear |
| Primary Fit | Trailers requiring an 86.5" hub-face TRUE 8K axle beam with 3.5" tube |
| Brake System | Compatible 8,000 lb electric brake assemblies, typically 12.25" x 3.375" |
| Hub / Drum System | Dexter 8-285 style drum/hub assemblies where all bearing, seal, and brake specifications match |
| Notes | Spring center must be verified and perches must be welded before the axle is placed into service. |
Included Components
| Quantity | Item |
|---|---|
| 1 | Dexter 8000-865-35-KIT trailer axle beam — 86.5" hub face, 3.5" tube, EZ Lube, 4-bolt brake flange |
| 2 | SS-350 spring perches for 3.5" axle beam — included loose |
Required Components Not Included
| Component | Specification / Note |
|---|---|
| Brake Assemblies | 8,000 lb electric brakes, typically 12.25" x 3.375" |
| Drums / Hubs | Dexter 8-285 style drum/hub assemblies where specifications match |
| Bearings | 25580 inner / 02475 outer |
| Seals | 2.25" ID typical; verify against the trailer and hub/drum setup |
| Suspension Hardware | U-bolts, plates, nuts, wheels, tires, brake wiring, and related mounting hardware are not included unless specifically listed. |
Spring Perches Are Included Loose
This listing includes the axle beam and two loose SS-350 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 axle. 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? | Yes. Two SS-350 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.
