Quick Product Specifications
| Specification | Detail |
|---|---|
| Brand | TRQ |
| TRQ part number | PSA66160 |
| Store number | 1ASBJ00130 |
| Interchange number | K500066 |
| Position | Front driver side lower |
| Quantity | One |
| Mounting type | Bolt-in |
| Adjustable | No |
| Greaseable | No |
| Dust boot included | Yes |
| Fitment | 2001–2005 Lexus IS300 |
| Warranty | Limited lifetime; exclusions apply |
Is K500066 the Driver or Passenger Side?
K500066 identifies the front driver-side lower ball joint.
The corresponding positions are:
- K500066 / TRQ PSA66160: front left, driver side
- K500067 / TRQ PSA66161: front right, passenger side
This listing includes only the driver-side component. If both original ball joints are worn, order the matching passenger-side joint or a complete two-piece set.
Reference and Interchange Numbers
The supplied reference numbers include:
- 43340-59065
- 43340-59066
- 43340-59135
- K500066
- MS86510
- SUS00188
- PSA66160
- 1ASBJ00130
These numbers represent OE references and aftermarket interchange identifiers. Verify the actual mounting pattern, housing shape and VIN rather than assuming every number represents an identical part from every manufacturer.
What Does the Lower Ball Joint Do?
The driver-side lower ball joint connects the lower suspension assembly to the steering knuckle. It allows the knuckle to pivot during steering and move with the suspension while maintaining controlled wheel positioning.
The joint supports:
- Steering articulation
- Suspension travel
- Wheel alignment
- Stable tire contact
- Predictable steering response
- Proper steering-knuckle location
The official Lexus parts catalog shows separate left- and right-side front lower ball-joint components for the first-generation IS300.
Symptoms of a Bad Driver-Side Ball Joint
A worn left lower ball joint may cause:
- Clunking from the driver-side front corner
- Popping while turning
- Loose or vague steering
- Vehicle wander
- Steering-wheel vibration
- Uneven left-front tire wear
- Alignment instability
- Grease leakage
- A damaged dust boot
- Excessive movement at the steering knuckle
Our guide to diagnosing a clunking noise over bumps explains why worn ball joints, sway-bar links and control-arm bushings are frequently mistaken for one another.
A click or pop during steering can also point toward joint wear. See the Pro Street guide to clicking noises while turning for a broader diagnostic process.
TRQ Design Features
The TRQ K500066 replacement uses an application-specific, bolt-in design that requires no vehicle modification for a confirmed IS300 application.
Key features include:
- Direct-replacement geometry
- Bolt-in mounting
- Sealed construction
- Preinstalled dust boot
- No external grease fitting
- Non-adjustable design
- Vehicle-specific driver-side housing
Because the joint is sealed and non-greaseable, routine lubrication is not required. Inspect the boot during normal suspension service. If it becomes torn or displaced, contamination can enter the joint even though the component itself cannot be serviced.
Will This Ball Joint Eliminate Front-End Noise?
It can eliminate noise caused by excessive movement in the driver-side lower ball joint. It will not repair:
- Worn control-arm bushings
- A loose sway-bar link
- Failed upper ball joint
- Worn inner or outer tie rod
- Damaged wheel bearing
- Weak shock or upper mount
- Loose brake hardware
Diagnose the suspension before replacing parts. A front-end clunk can travel through the chassis and sound as though it is coming from whichever component you inspected last.
If the steering wheel shakes, follow our guide to steering-wheel vibration causes before condemning the ball joint.
Replace One Side or Both?
Replacing K500066 alone can be appropriate when:
- Only the driver-side joint has measurable play
- The passenger-side joint passes inspection
- The left boot is damaged but the right boot remains intact
- One side sustained impact damage
Replacing both sides may be smarter when:
- Both joints are original
- The IS300 has high mileage
- Both boots show deterioration
- Both sides have measurable movement
- A complete suspension refresh is underway
The passenger-side joint has experienced the same age and mileage, although one side may wear faster due to potholes, road crowns or impact history.
Inspect the Rest of the Front Suspension
Before installing K500066, inspect:
- K500067 passenger-side ball joint
- Upper control arms and joints
- Lower forward-arm bushings
- Rearward caster-arm bushings
- Inner and outer tie rods
- Front sway-bar links
- Stabilizer-bar bushings
- Wheel bearings
- Steering-rack bushings
- Shocks and upper mounts
- Front tires
The Pro Street Energy Suspension guide explains how worn bushings allow unwanted movement that affects steering, braking stability and alignment.
Installation Considerations
TRQ promotes this component as a direct replacement, but “bolt-in” does not mean “impossible to install incorrectly.”
Typical tools include:
- Floor jack
- Properly rated jack stands
- Wheel chocks
- Metric sockets and wrenches
- Breaker bar
- Torque wrench
- Ball-joint separator
- Pry bar
- Pliers
- Penetrating oil
- Replacement cotter pin or locking hardware where required
Always lift the vehicle at approved points and support it securely. Never work under an IS300 held up only by a hydraulic jack. Read our guide on how to use an automotive jack safely before beginning.
Basic installation checks
- Verify that the component is PSA66160 or K500066.
- Confirm that it is being installed on the driver side.
- Compare the mounting pattern with the original joint.
- Support the steering knuckle during separation.
- Protect the brake hose and ABS wiring.
- Clean the mounting surfaces.
- Inspect the bolts and locking hardware.
- Torque every fastener to specification.
- Confirm that the dust boot is properly seated.
Do not use the mounting bolts to force an incorrectly positioned housing into place. If the holes do not align naturally, stop and verify the part.
Torque Specifications
Suspension hardware must be tightened to the correct factory specifications. Improper torque can cause loosening, thread damage or joint movement.
The Pro Street Lexus IS300 torque guide provides a useful chassis reference. Confirm the final values through factory service information for the exact model year and production date.
Replace cotter pins and other specified locking hardware rather than reusing damaged pieces.
Does the IS300 Need an Alignment?
A professional alignment check is recommended after lower-ball-joint replacement, particularly if connected suspension-arm hardware was loosened.
The alignment should verify:
- Toe
- Camber
- Caster
- Steering-wheel position
- Straight-line tracking
Repair all other loose suspension and steering parts before the alignment. Adjusting around a worn control-arm bushing merely makes the alignment temporary.
TRQ Limited Lifetime Warranty
TRQ states that this product is covered against defects in materials and workmanship for its usable lifetime when installed and operated as intended.
The stated exclusions include:
- Normal wear
- Misuse
- Abuse
- Collision or impact damage
- Improper application
- Unauthorized modification
Confirm the current terms, required documentation and remedy with the seller before purchasing. “Lifetime” refers to the warranty’s defined service period, not the eternal life of the ball joint. Sadly, suspension theology remains complicated.
Frequently Asked Questions
What years does TRQ PSA66160 fit?
It fits the 2001, 2002, 2003, 2004 and 2005 Lexus IS300, subject to production-date verification on early 2001 vehicles.
Is K500066 the left or right ball joint?
K500066 is the front-left lower ball joint for the driver side.
What is the passenger-side part number?
K500067 or TRQ PSA66161 is the corresponding passenger-side lower ball joint.
Does this listing include both sides?
No. It includes one driver-side ball joint.
Does it fit the IS300 SportCross?
The underlying K500066 application covers the 2002–2005 IS300 SportCross. Confirm the VIN through the seller’s vehicle fitment tool.
Is the ball joint adjustable?
No. It is a fixed OE-style replacement and does not provide camber adjustment.
Is it greaseable?
No. The TRQ specification identifies it as a sealed, non-greaseable joint.
Does it include a dust boot?
Yes. A protective dust boot is included.
Does it fit a 2006 Lexus IS250?
No. It fits the first-generation 2001–2005 Lexus IS300.
Is professional installation recommended?
Yes, particularly if the installer lacks proper lifting equipment, joint-separation tools or factory torque information.
Final Verdict
The TRQ PSA66160 is a straightforward bolt-in replacement for the front driver-side lower ball joint on the 2001–2005 Lexus IS300. It cross-references to K500066, includes a dust boot and uses sealed, maintenance-free construction.
Confirm the production date on early 2001 vehicles, inspect the matching passenger-side joint and surrounding bushings, follow the correct torque procedure and complete the repair with an alignment check.
There are no reviews yet.