What is the shelf life of automotive urea?

[McEsther]

Automotive urea is a pure but relatively unstable preparation, composed of 32.5% high-purity automotive urea and 67.5% ultra-pure water. Relevant information is as follows: 1. Urea: The storage period of automotive urea is 36 months when the temperature is ≤10℃, 18 months when the temperature is ≤25℃, and 12 months when the temperature is ≤30℃. 2. Recommendation: When using automotive urea, it is advisable to use products that have been manufactured within six months. If the product has been stored for more than one year, it is strongly recommended not to use it. The above refers to small packaged automotive urea solutions. Nowadays, there are automotive urea dispensers in many places, which are not only as convenient as refueling but also ensure the quality of the automotive urea.

[MacElizabeth]

I previously encountered issues with urea crystallization in my vehicle. Typically, the shelf life of barrel-stored urea is about one year, and it deteriorates more easily when stored in high temperatures during summer. Last year, my car displayed a fault code, and the mechanic said it was due to using urea that had been expired for half a year. Now, I store it in small portions in plastic water bottles and keep them in a cool place, which can extend the shelf life to 18 months. The key factor is the storage temperature—when it exceeds 25°C, the decomposition rate doubles, leading to white crystals that can clog the nozzle. For fellow diesel vehicle owners, I recommend checking the sediment in the urea tank in the trunk every six months.

[VonCassidy]

As a veteran long-haul driver with 20 years of experience, I've found that automotive urea is completely different from gasoline or diesel. Sealed containers from reputable brands can last 12-18 months, but once opened, they should be used within six months at most. Last month, I saw a fellow trucker's urea pump get completely clogged with crystallization—when opened, it was full of gravel-like white chunks. Here are three suggestions: don't stock up on large containers, avoid direct sunlight, and don't leave it in a vehicle below -11°C in winter. Remember, degraded urea can corrode the SCR system, and repairing a single nozzle can cost as much as ten barrels of urea.

[StephenLee]

When I first bought the car, the 4S store tricked me into hoarding three large barrels of urea solution. Now, the third barrel has turned yellow. A professional technician taught me a few methods to check: normally, it should be a transparent light blue liquid; a pungent ammonia smell indicates spoilage; if the foam doesn’t dissipate quickly after shaking, that’s also a bad sign; using a PH test strip, if it’s below 9, it should be discarded. Especially note that plastic barrels slowly allow air in, and once opened, the shelf life is halved. Now I’ve switched to buying small bottles—though more expensive, it’s worry-free.