Coolant & Radiator Cap Prices
Market data for 86,831 caps shows a median price of 19.88.
What you'll usually pay
👉 In short easy summary
The best value is found in Aftermarket Branded options, which sit 25% below the median. Genuine OEM parts command a premium, costing 21% more than the market average.
💚 Best value for your money
Price by brand type
Why? Prices range from Unbranded at 14.24 to Genuine OEM at 23.99.
Price by brand
Why? Mopar and Mr Gasket are the most expensive, while Dorman is the lowest at 17.12.
Price by type
Why? Radiator Caps are the most common at 19.99, while Coolant Overflow Reservoir Caps are the cheapest at 13.77.
🛒 Some on sale right now
Common questions
What is the price difference between new and used caps?
New caps have a median price of 19.77, while used caps are slightly higher at 19.99.
How much more do Genuine OEM caps cost compared to the median?
Genuine OEM caps have a median price of 23.99, which is 21% above the market median.
Which specific cap type is the most affordable?
Coolant Overflow Reservoir Caps are the most affordable with a median price of 13.77.
How we got these numbers
Worked out from 200 live eBay listings (price range $9–$47, odd outliers ignored). These are asking prices, so use them as a guide. Last checked August 12, 2026.