At a Glance
- SKU: CSRK-TA-WB-LE-BB-SW4B
PRODUCT INFORMATION
Product Details
Tandem Axle Suspension Rebuild Kit
Complete 3.5K Tandem Axle Suspension Rebuild Kit
Complete suspension rebuild kit for 3,500 lb tandem trailer axle applications using 25.25" double-eye leaf springs, 7-3/4" equalizers, shackles, wet bolts, bronze bushings, hangers, and U-bolt hardware.
Part Number: CSRK-TA-WB-LE-BB-SW4B 3.5K Tandem Axle Application Double-Eye Spring / Wet Bolt Kit
Overview
The CSRK-TA-WB-LE-BB-SW4B is a complete tandem axle suspension rebuild kit for compatible 3,500 lb trailer axle suspension setups. This kit brings together the major service parts commonly replaced during a full suspension overhaul, including four double-eye leaf springs, curved equalizers, frame hangers, shackle straps, greaseable wet bolts, flange nuts, bronze bushings, and U-bolt hardware.
R&P Service Insight
A worn tandem axle suspension can lead to sagging, loose tracking, uneven tire wear, excess shackle movement, poor equalizer action, and reduced towing confidence. Rebuilding the full suspension system helps restore geometry instead of chasing one worn part at a time.
- Complete Rebuild Approach: Designed to refresh springs, equalizers, shackles, bushings, bolts, hangers, and U-bolt mounting hardware.
- Wear-Point Coverage: Targets common tandem suspension wear areas including spring eyes, equalizer pivots, shackle straps, and bushing locations.
- Fitment Check Required: Always compare your existing suspension dimensions before ordering or installing.
R&P Knowledge Hub
Compatibility: Intended for compatible 3,500 lb tandem trailer axle suspension applications where the listed spring, equalizer, hanger, bushing, shackle, and U-bolt dimensions match.
Vehicle / System Fit: Tandem axle utility trailers, cargo trailers, equipment trailers, RV-style trailers, and similar double-eye leaf spring suspension systems.
Installation Notes: Verify spring length, spring width, equalizer length, hanger height, shackle strap length, bushing dimensions, axle tube size, and U-bolt configuration before installation.
Performance Insight: A full suspension rebuild can help improve load distribution, axle control, towing stability, braking consistency, and overall road feel.
Brand & Fitment Note
Selling Brand: R&P Carriages curated suspension rebuild kit.
Application Reference: Trailer, RV, axle, and suspension references in this listing describe compatibility or application style only where supported by matching measurements and configuration.
What This Means: This listing is for a complete R&P Carriages curated suspension rebuild kit, not a guaranteed OEM-branded item unless specifically stated and verified.
Before Ordering: Confirm axle rating, spring style, equalizer dimensions, hanger layout, shackle spacing, bushing size, axle tube size, and U-bolt fit before installation.
R&P Repair Insight
This kit is a strong choice when a tandem axle trailer shows suspension wear such as loose shackles, worn bushings, sagging springs, noisy equalizers, axle shift, or uneven ride height. Before disassembly, measure and document the original suspension layout so the new components can be installed in the correct orientation.
- Measure Before Removal: Record hanger spacing, axle position, equalizer orientation, and spring center locations before removing old parts.
- Inspect Mounting Points: Do not install new suspension components into cracked, stretched, or damaged frame hanger locations without correcting the frame issue first.
- Service Wet Bolts: Greaseable wet bolts should be installed correctly and maintained as part of regular trailer suspension service.
Features
Complete Tandem Axle Kit
Includes the main suspension components needed to rebuild a compatible 3.5K tandem axle double-eye leaf spring suspension setup.
Four SW4B Leaf Springs
Includes four SW4B double-eye leaf springs measuring 25.25" long, 1.75" wide, 4-leaf construction, and 1,750 lb rated each.
7-3/4" Equalizer System
Includes two EQ-E1 curved equalizers with a 7-3/4" length for compatible tandem axle suspension layouts.
Wet Bolt & Bronze Bushing Upgrade
Includes greaseable wet bolts, flange nuts, bronze bushings, shackles, hangers, and U-bolt hardware for a more complete suspension service.
Specifications
| Specification | Detail |
|---|---|
| Part Number | CSRK-TA-WB-LE-BB-SW4B |
| Brand | R&P Carriages curated kit |
| Product Type | Complete tandem axle suspension rebuild kit |
| Application | Compatible 3,500 lb tandem trailer axle suspension systems |
| Spring Style | Double-eye leaf spring |
| Spring Measurement | 25.25" long, 1.75" wide, 4-leaf construction |
| Spring Rating | SW4B leaf springs listed as 1,750 lb rated each |
| Equalizer | EQ-E1 curved equalizer, 7-3/4" long |
| Shackle Strap | SL-2.562, 2.562" hole center, 3.75" x 1.25" x .23" |
| Bushing | BU1-1566B bronze spring eye / equalizer bushing, 0.57" x 0.69" x 1.75" |
| Wet Bolt | FA-7-187, hex head wet bolt, 0.56" x 3", 7/16" step-down end |
| U-Bolt Hardware | BOM includes UBK-3500-R kit line plus individual 12N nuts, TP-4 tie plates, and UB-R301 round U-bolts as listed below |
Fitment / Application
| Category | Details |
|---|---|
| Vehicle / System | Tandem axle trailer suspension system |
| Primary Fit | Compatible 3,500 lb tandem trailer axle applications using double-eye leaf springs and matching 7-3/4" equalizer geometry |
| Secondary Fit | Utility trailers, cargo trailers, equipment trailers, RV-style trailers, and similar tandem axle suspension layouts where dimensions match |
| Important Fitment Note | Do not order by axle rating alone. Confirm spring length, spring width, equalizer size, hanger height, shackle length, bushing dimensions, axle tube size, and U-bolt configuration before installation. |
Included Components / BOM
| Quantity | Item |
|---|---|
| 14 | BU1-1566B: Bronze spring eye / equalizer bushing, 0.57" x 0.69" x 1.75" |
| 2 | EQ-E1: Equalizer, 7-3/4" |
| 14 | FA-6-92Z: 7/16" flange nut for greaseable shackle bolts / wet bolts |
| 14 | FA-7-187: Wet bolt, hex head, 0.56" x 3", 7/16" step-down end |
| 8 | SL-2.562: Shackle strap, 2.562" hole center, 3.75" x 1.25" x .23" |
| 4 | SW4B: Leaf spring, double eye, 25.25" long, 4 leaf, 1,750 lb rated each |
| 2 | UBK-3500-R: U-bolt kit, 3.5K, 5-1/2" long U-bolts with U-bolt plates |
| 8 | 12N: U-bolt nut, 1/2"-20 |
| 2 | TP-4: U-bolt tie plate |
| 4 | UB-R301: Round U-bolt, 3" x 6.5" x 1/2"-20 |
Verify all measurements, axle rating, suspension layout, spring length, spring width, equalizer length, hanger height, shackle length, bushing dimensions, axle tube size, U-bolt size, and included BOM components before installation. This kit should be used only where the listed components match the trailer being serviced.
CSRK-TA-WB-LE-BB-SW4B complete 3500 lb tandem axle suspension rebuild kit, 3.5K tandem trailer suspension kit, SW4B leaf spring kit, 25.25 inch double eye leaf spring kit, EQ-E1 7-3/4 inch equalizer kit, tandem axle wet bolt kit, bronze bushing suspension kit, trailer shackle hanger rebuild kit, tandem trailer suspension overhaul kit, UBK-3500-R U-bolt kit, UB-R301 round U-bolt, TP-4 tie plate, 12N U-bolt nut
Thank You For Choosing R&P Carriages As Your Online Shopping Source!
Related Parts & Kits
Check fitment, measurements, and kit contents before ordering. Related parts may not be required for your repair.
Looking up part numbers in our catalog…
Your repair list1 item selected
Selected products are added together. Review the cart and verify kit contents to prevent duplicates. Prices and discounts are determined at checkout.
BEHIND THIS LISTING
PHOTOGRAPHY & RESEARCH
Ariah Granados
DIGITAL PRESENTATION & DEVELOPMENT
Ken Martin
ONLINE SALES & QUALITY ASSURANCE
Rayn Fisher
WE’RE HERE TO HELP
Not sure it fits?
Have your SKU or manufacturer part number, photos of the original part and mounting, and any critical measurements ready. Capacity, voltage, or bolt pattern can help too.
815-357-3292 · 270 E Jackson St · Seneca, IL 61360
CUSTOMER REVIEWS
Leave a Google review
Good people. Real trailer work.
Customer feedback summarized from Google and Yellow Pages. Dates are shown where available.
TRAILER PARTSGOOGLE
Ordered trailer repair parts repeatedly; praised fast service, careful packing, and accurate orders.
RV KEYSGOOGLE
Found the correct RV keys at a good price with free shipping; the keys worked as expected.
AXLE & LEAF SPRINGSGOOGLE
Needed an unusual axle and leaf-spring size; the team listened and helped him sort out the fit.
PARTS & SHIPPINGGOOGLE
Praised the OEM and aftermarket selection, discounts, quick shipping, and friendly parts staff.
CUSTOM AXLEGOOGLE
Got the axle he needed right away, set up with a custom spring perch.
WELDINGGOOGLE
Praised the polite staff and quality welding on a project.
GAS STRUTGOOGLE
Replacement struts brought a long-used door back to working order.
CUSTOM TRAILERGOOGLE
Had a trailer built to his needs at a fair price, then found parts for two other trailers in stock.
CUSTOMER SERVICEGOOGLE
Praised the customer service after working with R&P over several years.
GAS SHOCKGOOGLE
Found the gas shock he wanted at a good price with shipping included.
CARGO TIE-DOWNGOOGLE
Received swivel D-rings with backing plates and praised the price, correct order, and service.
PARTS DELIVERYGOOGLE
The right parts arrived the first time, with fast delivery and helpful staff.
PROJECT HELPYELLOW PAGES
Said project advice and prompt shipping helped finish a trailer project.
SHIPPINGYELLOW PAGES
Reported helpful service and fast shipment to Germany.
SUSPENSION KITYELLOW PAGES
Praised a suspension kit, fair pricing, and good parts.
TRAILER CORDYELLOW PAGES
Was pleased with a replacement trailer cord.
SERVICE & PARTSYELLOW PAGES
Noted dependable service and products across repeat visits.
AXLE INSTALLATIONYELLOW PAGES
Said the axle installation fit perfectly and thanked Josh and the crew.
HITCH REPLACEMENTYELLOW PAGES
Praised the crew’s professionalism during a difficult hitch replacement.
PRICE & SERVICEYELLOW PAGES
Liked the product, price, communication, and shipping.
LISTING INFORMATIONYELLOW PAGES
Said the product description explained what would work for the trailer.
PRODUCT & SHIPPINGYELLOW PAGES
Received the item as described with very fast shipping and plans to return.
COMMUNICATION & SHIPPINGYELLOW PAGES
Praised accurate description, quick shipping, and clear communication.
PRICE & PRODUCTYELLOW PAGES
Was happy with the product and its price.
SELLER EXPERIENCEYELLOW PAGES
Called it a pleasure doing business with R&P.
INSTALLATIONYELLOW PAGES
Was pleased with product quality, quick delivery, and an easy installation.
PRODUCTSYELLOW PAGES
Was enthusiastic about the products.
DURABILITYYELLOW PAGES
Was ready to install the product on every trailer they own.
REPEAT CUSTOMERYELLOW PAGES
Expected to buy again after a good experience.
INSTALLED PARTYELLOW PAGES
Reported that the newly installed parts were working perfectly.
REPEAT CUSTOMERYELLOW PAGES
Said things went well, as they had on previous visits.
COMMUNICATION & VALUEYELLOW PAGES
Praised clear communication and fair value.
TRANSACTIONYELLOW PAGES
Said the transaction went as expected.
PRICE & PACKAGINGYELLOW PAGES
Noted good value, careful packing, and fast shipping.
PROFESSIONAL SERVICEYELLOW PAGES
Found the team professional and easy to work with.
COMMUNICATION & SHIPPINGYELLOW PAGES
Praised fast shipping and good communication.
TEAMYELLOW PAGES
Shared appreciation for the owners and their company.
SHIPPINGYELLOW PAGES
Reported prompt shipping and said they would buy again.
CUSTOMER SERVICEYELLOW PAGES
Found R&P easy to deal with.
SERVICEYELLOW PAGES
Praised the people and the service.
FIT & SHIPPINGYELLOW PAGES
Reported a good fit, fair price, accurate listing, and quick shipping.
DELIVERYYELLOW PAGES
Received the order a day early and recommended the seller.
CUSTOM TRAILERYELLOW PAGES
Described a no-hassle, professional custom-trailer purchase.
TRAILER PURCHASEYELLOW PAGES
Praised a new trailer, custom additions, helpful staff, and clear pricing.
HUB COVERSYELLOW PAGES
Found the right hub covers quickly and got helpful maintenance advice.
AXLE HELPYELLOW PAGES
Said R&P helped their company get back on the road after an axle problem.
DUMP TRAILERYELLOW PAGES
Was happy with a dump-trailer purchase after comparing options.
BRAKES, DRUMS & SEALSYELLOW PAGES
Received clear help choosing brake assemblies and bearing seals, followed by fast shipping.
DUMP TRAILERYELLOW PAGES
Found a good deal on a 16-foot dump trailer and planned to return.
FRIENDLY SERVICEYELLOW PAGES
Thanked the staff for their patience and recommended the shop.
Showing 3 of 50
Need help with this part? Send photos, part numbers, and measurements. We’ll help you narrow it down.