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Dorman 521-685 Rear Trailing Arm - Driver Side Suspension Component

(2015-2020 Ford F-150; 1999-2003 Mazda Protege; 2002-2003 Mazda Protege5)

Part of: Dorman Rear Trailing Arm

Other options in this family: Dorman 523-293 Dorman 522-290 Dorman 523-292 Dorman 524-452 Dorman 523-294

Manufacturer

Picture for manufacturer Dorman

Part Number

521-685
14 reviews
Sale Price

$26.72

In Stock (10+)

delivery box

Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Dorman 521-685 is a direct-replacement rear trailing arm designed for the driver side of your vehicle's suspension system. Trailing arms are critical suspension components that connect the axle to the chassis, controlling wheel motion and maintaining proper alignment during acceleration, braking, and cornering.

Key Features:

  • Direct-fit replacement for worn or damaged original trailing arm
  • Engineered to restore factory ride quality and handling characteristics
  • Rigorously tested by product and quality engineers for sustained performance
  • Designed to provide directional stability and responsive handling
  • Constructed to meet or exceed OE specifications for reliability
  • Driver side (left side) rear position application

Dorman's industry-leading evaluation process ensures this trailing arm delivers the secure performance and passenger safety expected from a critical suspension component. When original trailing arms become worn, bent, or corroded, they can compromise handling, alignment, and tire wear—making timely replacement essential for vehicle safety and performance.

Products specifications

Fits

2015-2020 Ford F-150; 1999-2003 Mazda Protege; 2002-2003 Mazda Protege5

Feature - Benefit 1

Bushings included for a complete installation, saving time and labor (where applicable)

Bushing Material

Rubber

Control Arm Type

Boxed

Package Contents

Suspension Trailing Arm

Pre Greased

Not Required

Ball Joint Installed

No

Grade Type

Regular

Ball Joint Included

No

Adjustable

No

Grease Fitting Included

Not Required

Material

Steel

Bushings Included

Yes

Easy

Product shipped in 3 days, but customer service did not know when I contacted on the 4th day. Received shipping confirmation on 5th day. Otherwise, smooth transaction, product arrived well packaged and fit perfectly. Great price.

Fast Fast Fast!!!!

So far so good.

Quick and Easy

This is my first time (but definitely not my last) to use Autoplicity. After doing several searches for the Air Lift helper springs Autoplicity beat everyone by at least 20 dollars. Another nice shock was they have very reasonable shipping rates.

nice

thanks

Good web store front. Makes Parts Geek look like the trainwreck it is.

you all do a fine job

Lets see how it goes

Best price for a product I've been shopping for, for months, and when I saw Autoplicity having it for A LOT cheaper, putting the product in my sweet spot price wise, I didn't hesitate to order. <br><br>My bank was a little slow to post the transaction, and I was suprised to get a human on the phone with no effort to make sure my order was properly processed. The gentleman I spoke with was very friendly and promptly answered all my questions. <br><br>Only the $5 I'm getting back for this review can make this deal any better, as I have no suggestion for improving the transaction I made with them.

Found what I wanted at a good price.

Had an error first time i ordered. Went smoothly next time.

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