# MotoRad 999-221 Engine Coolant Thermostat with Seal for 2005-2009 Audi A8

### Specifications

Bypass Diameter: 1.64"

Bypass Length: 1.58"

Gasket Type: O-Ring

Gasket/Seal Material: Rubber

Grade Type: Regular

Installation Tool Included: No

Material: Aluminum, Steel, Copper

Mounting Hardware Included: No

Mounting Hole Quantity: 7

Number Of Outlet Ports: 2

Number Of Seals: 1

Outlet Diameter: 1.50"; 1.14"

Temperature (Degree): 221F

### Features

-   Offer precise pressure control
-   Ensure the proper fit
-   Made of high quality materials
-   Easy installation

### Product Details

Engine Coolant Thermostat with Seal by MotoRad®. Temperature: 221F. State-of-the-art equipment, strict quality control, and functional testing to each thermostat ensure customers that they can trust the high-quality product used in their vehicle. As cooling system experts, MotoRad knows what is necessary to manufacture a high-quality part that will stand up to the rigors of today’s demanding cooling system environments where others fail.

MotoRad offers a full line of thermostats to replace original equipment thermostats. These parts are manufactured with high-grade duel bridge stainless steel construction and they meet or exceed all original equipment manufacturer requirements. MotoRad also offers standard thermostats in many alternate temperatures.

Brand: MotoRad

Part Number: 999-221

UPC: 055644999029

Alternate MPN: 999221

### Vehicle Fitment Table

Year

Make

Model

Position

Fitment Precision

Note

2005

Audi

A8

2006

Audi

A8

2007

Audi

A8

2008

Audi

A8

2009

Audi

A8

### FAQ

**Will this fit my vehicle?**  
Please verify your year, make, model, position, and any fitment notes using the Vehicle Fitment Table above before purchase.

**What part number is this?**  
The listed part number is 999-221.

**Is this product designed for direct replacement?**  
Yes. This product is intended to match the compatible vehicle applications listed in the fitment table.

**Should I confirm fitment before ordering?**  
Yes. Always compare your original part, position, and vehicle details with the fitment table before ordering.

### Common Searches

-   Engine Coolant Thermostat with Seal for Audi A8
-   999-221 fitment
-   MotoRad Engine Coolant Thermostat with Seal
-   2005 Audi A8 Engine Coolant Thermostat with Seal

## Details

- **Price:** 1404.1 CAD
- **Vendor:** MotoRad
- **Type:** Engine Coolant Thermostat with Seal
- **Tags:** 2005-2009 Audi A8, 999-221, Automotive, Engine Coolant Thermostat with Seal, MotoRad

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 1404.10 CAD | In stock |

## Images

- MotoRad 999-221 Engine Coolant Thermostat with Seal for 2005-2009 Audi A8

---

> Source: [Standard Auto Part](https://www.standardautopart.com/products/motorad-999-221-engine-coolant-thermostat-with-seal)
> Updated: 2026-08-17