HomeSuspension > Suspension, Springs and Related ComponentsWestar ST-3966 Coil Spring Insulator - Rear Upper
Part #: ST-3966

Westar ST-3966 Coil Spring Insulator - Rear Upper

Rear Upper
22 vehicles fit this part
Select your vehicle to confirm fitment
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OE Direct Replacement — Bolt-on fit, no modifications needed
Fitment: Ford and Mercury, Tempo and Topaz
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Rear Upper Coil Spring Insulator for Tempo and Topaz

Westar ST-3966 is a rear upper coil spring insulator built for 1984-1994 Ford Tempo and 1984-1994 Mercury Topaz applications. It helps isolate suspension movement, reduce road noise, and maintain proper spring-to-body contact in the rear upper position.

  • Provides a pivot point for suspension rotation to support correct suspension dynamics
  • Locks the strut and body together at the mounting point
  • Dampens noise and vibration from the road
  • Direct-fit replacement for rear upper suspension service on Ford Tempo and Mercury Topaz
  • Westar part number ST-3966 for application matching and catalog lookup

How ST-3966 Supports Suspension Performance

This coil spring insulator is designed for the rear upper suspension location on Ford Tempo and Mercury Topaz models. By separating metal contact points and helping the suspension rotate as intended, ST-3966 supports steering response, helps limit uneven tire and component wear, and reduces vibration transfer into the cabin. This part cross-references Monroe Shocks & Struts (e.g., 903966) for the same application.

What This Part Helps Address

  • Clunking or squeaking from the rear upper suspension area
  • Excess road noise entering the vehicle
  • Vibration felt through the body or chassis
  • Wear caused by direct metal-to-metal contact at the spring seat
  • Suspension movement that is no longer isolated properly

Installation Notes and Fitment

Compatible with 1984-1994 Ford Tempo, rear upper, and 1984-1994 Mercury Topaz, rear upper. Confirm the rear upper position before installation and inspect adjacent suspension components for wear while servicing the spring area. Westar ST-3966 is commonly searched as a rear upper coil spring insulator for Ford Tempo and Mercury Topaz suspension repair.

Quality Assurance

Westar uses application-specific materials and a protective finish intended to support part durability and appearance over time. ST-3966 is built to meet the needs of the listed rear upper fitments and to provide consistent suspension isolation in service.

BrandWestar
Part NumberST-3966
Bullet 1Provides a pivot point for the suspension to rotate on, to allow
Bullet 2Provides a locking mechanism to lock the strut and body together
Bullet 3Provides a noise dampening system to prevent noise and vibrations

This part fits 22 vehicles. Search below:

YearMakeModelPositionNotes
1994FordTempoRear Upper
1994MercuryTopazRear Upper
1993FordTempoRear Upper
1993MercuryTopazRear Upper
1992FordTempoRear Upper
1992MercuryTopazRear Upper
1991FordTempoRear Upper
1991MercuryTopazRear Upper
1990FordTempoRear Upper
1990MercuryTopazRear Upper
1989FordTempoRear Upper
1989MercuryTopazRear Upper
1988FordTempoRear Upper
1988MercuryTopazRear Upper
1987FordTempoRear Upper
1987MercuryTopazRear Upper
1986FordTempoRear Upper
1986MercuryTopazRear Upper
1985FordTempoRear Upper
1985MercuryTopazRear Upper
1984FordTempoRear Upper
1984MercuryTopazRear Upper

* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.

This part directly replaces or is cross-referenced with the following part numbers:

703966

Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.