Apex Chassis ProLock Drag Link Kit — Ford F-250/F-350 Super Duty (7075-T6 Polished Aluminum) SKU: KIT371

Verified Fitment

This kit is not compatible with wide-track axle configurations. Confirm your axle is a standard-track unit before ordering.

Component Specifications

What Is and Is NOT Included

Included:

• Complete ProLock Drag Link assembly (drag link end DL318 for 05–16 application)
• 2" 7075-T6 polished aluminum adjusting rod
• Drag link ends with ProLock keyway machined into threads
• ProLock keyway washers
• Jam nuts with integrated set screws
• Reversible stainless steel taper sleeve
• Grade 8 / Class 10.9 hardware, castle nuts
• Zerk fittings (pre-threaded, pre-greased)

Not included:

• Replacement set screws (sold separately, part number XP172)
• Steering stabilizer (sold separately; see Critical Compatibility for compatible options)
• Wrench kit required for installation — aluminum assembly requires KIT524 (WR113 46mm/50mm and WR114 46mm/55mm), sold separately
• Thread locker (blue Loctite 243 or blue Permatex 24206 recommended; not included)
• Anti-seize compound (for adjusting sleeve threads; not included)

Critical Compatibility

• Wide track: This kit is NOT compatible with wide-track axle configurations. Confirm standard-track before ordering.
• BDS Adjustable Trackbar: This drag link is NOT compatible with the BDS Adjustable Trackbar. The adjuster sleeve on the BDS unit will contact the Apex drag link during operation.
• Steering stabilizer mounting: High-mount steering stabilizers must be mounted in the OE position at the taper hole in the pitman-arm-side drag link end. Apex recommends OE-style stabilizers, including Fox Part 985-24-001 and Carli. Through-shaft stabilizers such as the Fox ATS are not recommended.
• Lifted trucks: A numeric lift-height range is not published by Apex for this kit. On modified-height trucks, confirm steering geometry, drag-link adjustment, stabilizer position, and all clearance requirements during professional installation and alignment.
• Minimum engagement mark: The drag link end threads include a minimum engagement mark. If that mark is visible, thread engagement is below the safe minimum. Adjust the sleeve position between the two ends or address lift height as required.

Installation Notes

Safety warning: Steering is a critical safety component. The installer must read and follow the provided installation instructions in full before beginning. Failure to follow these instructions may result in loss of vehicle control, accident, and injury. Failure to use correct installation tools or follow correct procedures may also void the warranty. Installation instructions must be present through the full installation process, including alignment.

Required tools — aluminum assembly (this SKU):
Apex wrench kit KIT524 — WR113 46mm/50mm and WR114 46mm/55mm (sold separately)

Required consumables:

• Medium-strength thread locker (blue Loctite 243 or blue Permatex 24206 or equivalent)
• Anti-seize compound (for inside threads of adjusting sleeve only — do not apply to drag link end threads)
• High-pressure lithium grease

Installation summary:

1. Before removing the OEM drag link, measure from the center of the ball studs on each side and record those measurements. Note: the passenger side uses an eye, not a ball stud — measure from the inner edge of the eye to the opposite ball stud.
2. Apply anti-seize to the inside threads of the adjusting sleeve only. Do not apply anti-seize to the drag link end threads. Anti-seize in the jam nut area will reduce jam nut effectiveness.
3. Install the ProLock keyway washer onto drag link end DL318 (05–16) with the bent side facing toward the adjusting sleeve. Repeat on the opposite end DL317 with the bent side toward the adjusting sleeve.
4. Thread the drag link ends into the adjusting sleeve in the correct thread direction until each reaches the jam nut. Rotate the adjusting sleeve to set the length to the recorded center-to-center measurement. Adjust both ends equally to maintain proper thread engagement.
5. Thread the jam nuts all the way down the drag link ends.
6. Remove the OEM drag link assembly.
7. Apply a light layer of grease to the top of the boot before installation to reduce friction between the boot and the joint.
8. Install the new drag link — passenger/knuckle side first, then pitman arm side. Torque both fasteners to 75–82 ft-lbs. If the castle nut hole does not align, continue tightening until cotter pin installation is possible. Leave jam nuts loose at this stage.
9. With tires pointing straight ahead, center the steering wheel by rotating the adjusting sleeve.
10. Apply medium-strength thread locker under the jam nuts. Once the steering wheel is confirmed straight, tighten the jam nuts and torque to 200 ft-lbs.
11. Test steering lock-to-lock and confirm no interference with wheels or other vehicle components.
12. Install Zerk fittings. Grease with high-pressure lithium grease — ½ to 1 pump per fitting only. Over-greasing will cause the boots to balloon and fail.
13. Have a professional complete a full alignment before driving.
14. After alignment is complete, apply thread locker to all set screws and torque to 8–10 ft-lbs.
15. After alignment and torquing, tap ProLock keyway washers onto the adjusting sleeve with a hammer.
16. Use a paint marker to mark across the jam nuts and adjusting sleeves as a visual indicator of movement. Check jam nuts for tightness at 500 miles. Continue to check every 5,000 miles or at every oil change.

The Obsidian Take

This polished aluminum variant of the KIT371 replaces the factory Ford F-250/F-350 Super Duty (2005–2016) drag link with the same forged SAE 1045 steel housing, SAE 4140 chromoly ball studs, and ProLock system as the black aluminum version — with a polished raw aluminum rod finish in place of powder coat. The ProLock system uses a machined keyway, ProLock keyway washer, and a jam nut with integrated set screws, designed to help secure the drag-link connection against loosening. All fitment exclusions, compatibility restrictions, and installation requirements are identical to the black aluminum variant. Select this variant for polished aesthetics; the underlying specification is the same.

This Product Is For You If

• You own a 2005–2016 Ford F-250 or F-350 Super Duty, 4WD, standard-track configuration.
• You want to replace worn or underperforming OE drag-link components.
• You want a drag-link assembly with Apex's ProLock system designed to help secure the connection against loosening.
• You are running an OE-style steering stabilizer in the OE taper-hole position (Fox 985-24-001 or Carli recommended).
• You prefer polished aluminum aesthetics over black aluminum or DOM steel (other variants available).
• You are prepared for a professional-level installation that includes specific torque requirements, thread locker, anti-seize, and a required post-installation alignment.

This Product Is Not For You If

• Your Ford F-250 or F-350 Super Duty has a wide-track axle configuration.
• You are running a BDS Adjustable Trackbar — contact interference with the Apex drag link is a documented incompatibility.
• You are running a through-shaft steering stabilizer such as the Fox ATS.
• Your vehicle is not a 2005–2016 Ford F-250 or F-350 Super Duty, 4WD.
• You are on a modified-height vehicle and have not confirmed steering geometry, drag-link adjustment, and clearance requirements with a qualified installer.
• You do not have the required Apex wrench kit (KIT524 for aluminum assembly) or are not prepared to obtain one before installation.
• You prefer black aluminum or DOM steel — other variants are available for this application.

Product Family Reference

The KIT371 ProLock Drag Link Kit is available in multiple adjusting rod materials for the same Ford F-250/F-350 2005–2016 4WD, standard-track application. For the 2017–2026 Ford F-250/F-350 generation, see the KIT373 family. Confirm specifications for each variant against its own product documentation.

Common Questions

What is wide track, and how do I know if my truck has it?
Wide-track axles have a wider-than-standard front track width. Confirm your front axle track designation with your dealer or a qualified shop before ordering.

I have a lifted truck — does this kit fit?
Apex does not publish a specific lift-height range for this kit. Confirm steering geometry, drag-link adjustment, stabilizer position, and clearance during professional installation and alignment on any modified-height application.

What makes the ProLock system different from a standard drag link?
The ProLock system uses a machined keyway on the drag link end threads, a precision-cut ProLock keyway washer, and a jam nut with integrated set screws, designed to help secure the drag-link connection and reduce the risk of loosening under load.

Do I need special tools?
Yes. The aluminum assembly (this SKU) requires Apex wrench kit KIT524 — WR113 46mm/50mm and WR114 46mm/55mm — sold separately. Installation also requires medium-strength thread locker, anti-seize compound, and high-pressure lithium grease, which are not included.

Is a professional alignment required?
Yes. Apex's installation instructions require a professional alignment before the vehicle is driven after installation.

How often should I check the jam nuts?
At 500 miles after installation, and then every 5,000 miles or at each oil change. Use a paint marker across the jam nuts and adjusting sleeve as a visual indicator of any movement.

My pitman arm end is inverted from lifting — can I still mount a steering stabilizer?
Yes. The included stainless steel taper sleeve is reversible, allowing stabilizer mounting from either side of the drag link end.

Which steering stabilizer is compatible?
Apex recommends OE-style stabilizers — Fox Part 985-24-001 or Carli. Mount in the OE taper-hole position on the pitman-arm-side drag link end. Through-shaft stabilizers such as the Fox ATS are not recommended.

What are the replacement set screws if mine wear out?
Replacement set screws are Apex part number XP172, sold separately.

What is the warranty?
Apex covers manufacturer defects, premature wear, and breakage for the life of the vehicle, as long as the original purchaser owns the vehicle, with product registration required within 90 days of purchase. See full warranty summary below.

Manufacturer Data Disclaimer

Fitment, specification, compatibility, installation, and warranty data for this kit are sourced from Apex Chassis manufacturer product documentation and installation instructions, and OFAS-verified product data current as of publication. Specifications are subject to change without notice; confirm current documentation for this SKU at the time of purchase.

Required Legal, Warning, Fitment, and Return Notices

Safety Warning: Steering is a critical safety component. The installer must read and follow the provided installation instructions in full. Failure to follow these instructions may result in loss of vehicle control, accident, and injury. Failure to follow installation instructions and use correct installation tools may also void the warranty.

Warranty Summary: Apex Chassis warrants this product against manufacturer defects, premature wear, and breakage for the life of the vehicle, provided the original purchaser continues to own the vehicle. The product must be purchased through Apex Chassis directly or through an authorized Apex dealer, and must be registered with proof of purchase within 90 days of purchase. Products not registered within 90 days are covered only for 90 days from the date of purchase. Apex will, at its sole discretion, replace the defective part and cover ground shipping, or refund the original purchase price. Labor for removal or reinstallation is not covered. This warranty does not cover cosmetic imperfections, boots, bushings, or Heim-style joints, which are considered regular wear items. The warranty is void if the component is improperly installed, modified, or used in an application for which it was not designed, as determined at Apex's sole discretion. This warranty is governed by the laws of the State of Arizona.