DEI Radiator Relief Coolant Additive - 16 oz

DEI Radiator Relief coolant additive - improves heat transfer to reduce coolant temperatures by up to 30F, with a built-in corrosion inhibitor and anti-foaming agent that balance pH and reduce scale build-up. Compatible with all antifreeze types and water, and safe for cast iron, copper, brass, and aluminum. Dose: 1 oz per quart of coolant. 16 oz.

Specifications

Documents: Installation Instructions (PDF) | Material Safety Data Sheet (PDF)

Shipping

• In-stock orders placed before 3 PM EST ship the same day — everything else ships within 24 hours.
• Standard, expedited, and overnight options at checkout.
• Oversized items ship by freight and take longer.
• Backordered items ship as soon as stock lands — contact us for lead times.
• International orders: prices do not include VAT, duties, or import fees. Your country charges these at import and they are the buyer’s responsibility.

Returns

• 30-day returns on new, uninstalled items in original packaging with all hardware.
• Standard returns: 8% restocking fee, buyer pays return shipping. Both waived if the item is defective or we made the error.
• Installed or used parts can’t be returned — confirm fitment before you install.
• Special orders and custom items are final sale.
• Email us for return authorization before shipping anything back.

Full details: Shipping Policy · Refund Policy