# Proform 66756 | Exhaust Header Bolt; Universal; Proform 66756 Header Bolts; Hex Head; 3/8-16 X 1inL

### PROFORM 66756 APPLICATION SPECS:

Exhaust Header Bolt; Universal; 3/8 - 16 Inch Thread Size; 1 Inch Length; Locking Bolt; Hex Head; Black Oxide; Steel; With Wedge Locking Washers; Set Of 16

Each PROFORM® Grade 8 Header Bolt is permanently assembled with a pair of special washers. When the bolt is torqued to 28+ Foot-Pounds, the washers’ super-hardened external teeth bite into and grip the bottom of the bolt head and the top surface of the header. After being self-locked in this manner, any bolt-loosening rotation is blocked by a wedge-locking action created by the washers’ interfacing, matching cams. It’s an uphill climb: vibration that might ordinarily loosen the bolt actually increases the wedge-locking tension, securing the bolt even more. Because this simple wedge-locking method uses tension instead of friction, contact with oil actually facilitates the wedge effect. When changing headers, PROFORM Header Bolts can be untightened with a normal wrench, lubricated, and reused.

-   Bolt Type: Universal
-   Head Type: Hex Head
-   Head Size: 3/8 Inch
-   Thread Size: 3/8 Inch-16
-   Length (IN): 1 Inch
-   Finish: Black Oxide
-   Color: Black
-   Material: Steel
-   Washer Type: Wedge Locking

### FAQ

**What part number is this?** The listed part number is 66756.

**Is this product designed for direct replacement?** Confirm the original part specifications and intended application before ordering.

**Should I confirm compatibility before ordering?** Yes. Compare the original part and specifications before ordering.

### Common Searches

-   Proform 66756
-   66756 specifications
-   Proform Exhaust Header Bolt; Universal; Proform 66756 Header Bolts; Hex Head; 3/8-16 X 1inL

## Details

- **Price:** 129.86 CAD
- **Vendor:** Proform
- **Type:** Exhaust Header Bolt
- **Tags:** 66756, Exhaust Header Bolt, Proform

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 129.86 CAD | In stock |

## Images

- Proform 66756 | Exhaust Header Bolt; Universal; Proform 66756 Header Bolts; Hex Head; 3/8-16 X 1inL

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> Source: [Standard Auto Part](https://www.standardautopart.com/products/66756-vp-proform-518)
> Updated: 2026-10-21