Winter Weather & DEF: What Your Heavy Equipment Needs to Stay Productive
Cold temperatures can take a toll on Diesel Exhaust Fluid (DEF) and on your uptime. Here’s what operators and fleet managers should know before winter hits.
When the temperature drops, DEF becomes one of the most common cold-weather trouble spots on construction sites. But with the right storage and handling practices, you can keep your heavy equipment running smoothly all season long.
1. Know the Freezing Point
DEF begins to freeze at 12°F (-11°C). Most late-model machines include built-in heating elements to keep DEF warm during operation. If you’re running older equipment or machines without heated DEF systems, plan for a quick inspection before startup to make sure everything is in good shape.
2. Store DEF Properly
For best results, keep DEF between 12°F and 86°F. If it freezes in storage or inside the machine, don’t worry, it can be thawed safely. Just be sure to let it return to liquid form naturally. Never apply external heat or additives to speed up the process.
3. Leave Room for Expansion
When DEF freezes, it expands. If your machines sit outside overnight, avoid topping off tanks completely. Leaving a little space prevents cracking, leaks, and tank damage. And if it does freeze? Simply allow it to thaw on its own.
4. Watch for Changes in DEF Quality
Cold exposure can shorten DEF’s lifespan. A quick visual check can tell you if there’s a problem:
- Healthy DEF = clear or slightly blue
- Cold-affected DEF = cloudy, milky, or white (from temporary urea crystals)
Once DEF warms up, it should return to normal. If it stays cloudy or discolored, that may indicate contamination, and it’s best to replace it to avoid Selective Catalytic Reduction (SCR) system issues.
5. Use the Right Equipment for Handling & Dispensing
Insulated dispensing systems can keep DEF liquid longer and help prevent frozen lines on the jobsite. On newer Volvo excavators, operators will also find upgraded DEF sight gauges and splash guards designed to reduce misfueling and contamination, small details that make a big difference in winter.
6. Keep Heavy Equipment Warm When You Can
Parking in a heated shop or even a semi-protected area can dramatically reduce DEF-related headaches. Your machine will start more easily, and your DEF will already be at an ideal temperature for operation.
Stay Winter-Ready With Ascendum Machinery
DEF issues can slow down a jobsite fast, especially when temperatures stay below freezing. By following these winter best practices, you can help protect your equipment and keep your fleet productive when it matters most.
Want even more expert guidance? Check out Volvo CE’s full article on cold-weather DEF tips to go deeper into best practices and troubleshooting or schedule your winter service with Ascendum Machinery today!
