Certified Auto Pro Oil and Fuel System UV Dye Leak Detection for Cars & Trucks & More, 1 Oz, 374CS, Universal

It worked as advertised and helped me find a hidden oil leak from a hard to see place (only with a small mirror, a flash light, and lots of patience).

Made my oil glow, and my driveway! Worked Great!

I finally found my oil leak using this product. The only downside is you need a special UV light to even see it. Very cheap too! But other than that 100% would recommend for oil leaks.

Looks more orange than yellow in engine oil under a black light with yellow glasses on. Ends up almost the same color as Dexcool coolant. Would be more helpful if it was actually yellow looking. Otherwise works like dye should.

Used to diagnose an oil leak on a Polaris 570 Sportsman. Found both leaks within minutes of running this dye.

I had a mysterious oil leak on my side by side leave a puddle. Hard to tell where it came from, because I changed all the fluids and the oil was clear/clean. The engine was gritty and sticky. All kinds of possible areas where it might be leaking. I had visions of my engine being ruined in my head and hours of investigating to do.I heard about this product. You just put a little bit in your oil and run the engine. Then, shine a UV light(not included, but they sell UV flashlights) and the area leaking glows bright neon yellow. This works great! My issue ended up being weaping line off the water pump. I never would have checked there! I also got the peace-of-mind confirmation that all the other gaskets and seals were tight.It works great, especially in dark engine bays…because the dye glows like black light paint. It’s not subtle. It glows under the UV light. Cleans up with brake cleaner and a rag for future testing.I don’t know what I did without this. I’m telling everybody about this now.

I have an engine oil leak. Added the product to the oil. Used a black light. Never seen any illumination of product from the oil leak. So... I really cannot say whether it really worked or not. It did not help me out on this instance in finding where the leak was coming from.

Worked perfectly to help find a leak in one of the injectors on my Kubota tractor. I had been smelling raw diesel fuel and seeing some wet spots on the garage floor. Easy to use. Added dye, ran tractor for 10 minutes, used my ultraviolet flashlight and yellow tint shooting glasses to easily find the leak around the #3 injector. Make sure you turn off all lights except the ultraviolet, and dye shows as a nice, bright whitish-yellow. For under ten dollars it was well worth the money.