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UFP

UFP - Left Hand - 3700 lb Trailer Disc Brake Torsion Arm End Unit 59 Spline 5 on 4.5 (43039LU)

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At a Glance

  • SKU: 43039LU
PRODUCT INFORMATION

Product Details

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TRAILER TORSION AXLE HUB & SPINDLE ASSEMBLY

UFP - Left Hand - 3700 lb Trailer Disc Brake Torsion Arm End Unit 59 Spline 5 on 4.5

Part Number: 43039LU (Replaces 250-51014)

Genuine UFP 3,700 lb rated trailing torsion arm spindle and hub assembly featuring a 59-ridge spline, 5 on 4.5" bolt pattern, and integrated 1-3/8" x 1-1/06" tapered spindle.

SKU: 43039LU 3,700 LBS CAPACITY 59 SPLINE RIDGES
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Specifications
Specification Detail
Part Number / SKU 43039LU (Replacement for 250-51014)
Brand UFP Trailer Parts
Product Type Trailer Torsion Arm Spindle & Hub Assembly
Spline Count 59 Ridges (Peaks)
Spindle Size 1-3/8" x 1-1/16" Tapered
Diameter & Bolt Circle 9-3/4" Diameter | 5 on 4-1/2" Bolt Pattern
Capacity / Rating 3,700 Lbs.
Bearings & Races Inner: L68149 (Race L68110) | Outer: L44649 (Race L44610)
Seal Dimensions 1.68" ID x 2.56" OD
Mounting Hardware 5/8" Torsion arm mounting bolt, nut, and washer included
Fitment / Application
Category Details
Vehicle / Trailer / System UFP Torsion Axle Systems
Primary Fit Direct replacement for UFP Part # 250-51014
Secondary Fit / Common Use Marine & Utility trailers equipped with 3,700 lb UFP splined torsion arm axles
Fitment Method Splined torsion arm attachment (59-tooth pattern) secured via 5/8" bolt
Important Note Verify spline ridge count (59) and spindle taper dimensions prior to ordering.
R&P Knowledge Hub

Compatibility: Replaces UFP 250-51014. Fits 5-bolt wheels on a 4-1/2" bolt pattern.

Vehicle / System Fit: Designed for marine and general cargo trailers utilizing UFP 3,700 lb splined torsion axles.

Installation Notes: Torque the included 5/8" mounting bolt to manufacturer specifications during arm attachment. Inspect bearings and pack with fresh high-temp marine grease prior to final hub assembly.

Pro Insight: Exact spline count is critical on UFP trailing arms; always count individual ridge peaks on your original spindle to ensure proper 59-spline mating.

Features

  • Genuine UFP Trailer Parts construction
  • Precision-machined 59-ridge splined shaft
  • Rated for up to 3,700 Lbs. total axle capacity
  • Includes inner (L68110) and outer (L44610) bearing races pre-installed
  • Supplied with 5/8" torsion arm mounting bolt, washer, and lock nut

    Included Components

    Quantity Item
    1 UFP Splined Spindle & 9-3/4" Hub Assembly (5 on 4.5")
    1 Inner Bearing Race L68110 (Pre-Installed)
    1 Outer Bearing Race L44610 (Pre-Installed)
    1 Set 5/8" Torsion Arm Mounting Hardware (Bolt, Nut, Washer)
    Important Fitment Note: Please verify all spindle dimensions, spline ridge counts (59 peaks), hub bolt patterns (5 on 4.5"), and bearing inner/outer series before completing purchase. OEM references (such as 250-51014) are provided strictly for direct application and fitment cross-referencing.

    UFP Trailer Parts 43039LU 250-51014 3700 lbs torsion arm spindle hub assembly 59 spline 5 on 4.5 bolt pattern L68149 L44649 L68110 L44610 marine trailer torsion spindle hub kit 1-3/8 x 1-1/16
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