At a Glance
- SKU: UB-R303-ZP
PRODUCT INFORMATION
Product Details
Round Zinc Plated U-Bolt 3" x 9/16" Diameter x 7" Long Fine Thread Grade 5 (UB-R303-ZP)
Part # UB-R303-ZP
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Trailer Axle U-Bolt / Suspension Hardware
Round Zinc Plated U-Bolt 3" x 9/16" Diameter x 7" Long Fine Thread Grade 5
Silver zinc plated metal round U-bolt for compatible trailer axle and suspension applications where a 3" inside width, 9/16" diameter, 7" long U-bolt is required.
SKU: UB-R303-ZP 3" x 9/16" Dia. x 7" Long Fine Thread / SAE Grade 5
Key Measurements & Specs
| Specification | Detail |
|---|---|
| SKU | UB-R303-ZP |
| Product Type | Round trailer axle U-bolt |
| Size | 3" x 9/16" diameter x 7" long |
| Thread Type | Fine thread |
| Threads Per Inch | 18 TPI |
| Grade | SAE Grade 5 |
| Material / Finish | Metal, zinc plated |
| Color | Silver |
| Quantity Included | 1 U-bolt |
Fitment / Application
| Category | Details |
|---|---|
| System | Trailer axle and suspension hardware |
| Application Reference | Fits compatible 7000# applications where measurements and hardware match |
| Matching Thread | 9/16"-18 fine thread |
| Related Hardware Reference | UBN-9C / TP-4 reference where correct for the application |
| Fitment Method | Verify axle tube size, U-bolt width, bolt diameter, length, plate fitment, and nut thread before ordering |
Top Features
| Feature | Buyer Benefit |
|---|---|
| Zinc Plated Finish | Silver finish provides corrosion-resistant surface protection for trailer hardware use |
| 9/16"-18 Fine Thread | Matches compatible fine-thread nuts and suspension hardware |
| SAE Grade 5 | Built for heavier-duty trailer suspension fastening applications where Grade 5 hardware is specified |
| 3" x 7" Size | Useful for compatible axle tube and U-bolt plate setups requiring this measurement |
Overview
This listing is for one round zinc plated U-bolt, SKU UB-R303-ZP. The U-bolt measures 3" x 9/16" diameter x 7" long and uses 9/16"-18 fine thread. It is SAE Grade 5 hardware with a silver zinc plated finish for compatible trailer axle and suspension applications.
R&P Service Insight
U-bolts must be matched by measurement and thread, not by appearance alone. Before replacing axle hardware, confirm the complete suspension stack matches this 3" width, 9/16" diameter, 7" length, and 18 TPI thread requirement.
- Measure First: Confirm U-bolt width, diameter, and overall length before ordering.
- Thread Match: This U-bolt uses 9/16"-18 fine thread.
- Hardware Match: Confirm the nut and plate match the U-bolt size and thread before installation.
R&P Knowledge Hub
Compatibility: Use for compatible 7000# trailer axle applications where the existing U-bolt dimensions, thread, and related hardware match.
Vehicle / System Fit: Trailer axle and suspension hardware applications using a round 3" x 9/16" diameter x 7" long U-bolt.
Installation Notes: Verify axle tube size, U-bolt plate, nut thread, and length before installation. Replace worn or mismatched suspension hardware as needed.
Performance Insight: Correct U-bolt size and thread engagement are critical for proper axle clamping and suspension hardware alignment.
Brand & Fitment Note
Selling Brand: R&P Carriages
Application Reference: 7000# application references are fitment guides only. Final fit depends on matching the U-bolt measurements and related suspension hardware.
What This Means: This listing is for one R&P Carriages round zinc plated U-bolt, not a complete U-bolt kit unless specifically stated.
Before Ordering: Verify measurements, thread pitch, axle tube size, plate compatibility, nut compatibility, and included components before installation.
R&P Repair Insight
When servicing trailer suspension hardware, U-bolts should be selected by exact measurement and thread specification. A mismatch in diameter, length, thread pitch, or plate fit can prevent proper installation.
- Width Check: Confirm the 3" U-bolt width matches the axle tube and plate setup.
- Thread Check: Confirm the mating nuts are 9/16"-18 fine thread.
- Length Check: Confirm the 7" length provides the correct fit for the spring stack and plate arrangement.
Features
Round U-Bolt Design
Designed for compatible round trailer axle and suspension fastening applications where this size is required.
9/16"-18 Fine Thread
Fine-thread 9/16" diameter hardware with 18 threads per inch for matching compatible nuts.
SAE Grade 5 Hardware
Grade 5 specification for compatible trailer suspension applications requiring this hardware grade.
Silver Zinc Plated Finish
Zinc plated metal construction with a silver finish for clean appearance and surface protection.
Included Components
| Quantity | Item |
|---|---|
| 1 | Round zinc plated U-bolt, 3" x 9/16" diameter x 7" long, 9/16"-18 fine thread |
| Not Included | Nuts, plates, washers, and additional suspension hardware unless separately selected or stated |
Important Fitment Note: Verify all measurements, thread pitch, axle tube size, U-bolt plate fitment, nut compatibility, and included components before installation. This listing is for one U-bolt only unless otherwise stated.
UB-R303-ZP round zinc plated U bolt, 3 inch 9/16 diameter 7 inch long U bolt, 9/16-18 fine thread U bolt, SAE Grade 5 trailer axle U bolt, silver zinc plated metal U bolt, 7000 lb trailer axle U bolt, UBN-9C compatible thread reference, TP-4 trailer suspension hardware reference, R&P Carriages trailer axle suspension hardware
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