If you're traveling a modern diesel truck in the particular dead of winter season, you've probably considered how to keep DEF fluid from freezing when the temperature starts to tank. It's one of these things that doesn't cross your thoughts in July, yet the moment that 1st frost hits, this becomes a major worry. Diesel Exhaust Fluid (DEF) is mostly water—about 67. 5% to be exact—which indicates it behaves a lot like drinking water when it gets cool. After the thermometer strikes 12 degrees F (-11 Celsius), that jug of DEF within your garage or the tank within your truck is certainly going to turn into a slushy clutter or a strong block of snow.
The good news is that engineers actually made up this when these people designed modern SCR (Selective Catalytic Reduction) systems. But while your truck might be looking forward to the particular cold, you continue to require to know the few tricks to make sure you don't end up with cracked lines, a deceased pump, or even a vehicle that's stuck in limp mode.
Understanding the expansion factor
The greatest problem with freezing DEF isn't actually the ice alone; it's the development. Just like a bottle associated with water will burst if you leave it within the freezer over night, DEF expands by about 7% when it solidifies. In case your tank is filled right up to the top and that fluid freezes, there's nowhere with regard to it to go. This is how you end up with damaged plastic tanks or damaged sensors.
Among the easiest ways to prevent damage is to avoid topping out of your DEF tank whenever a cold take is coming. Usually, we like to keep our storage containers full to prevent condensation, using DEF in the winter season, you would like to depart a little bit of breathing room. Most manufacturers recommend keeping the container around 75% to 80% full in case you expect a hard freeze. That extra space provides the fluid room to expand upward with no putting pressure for the walls of the particular tank or the pump assembly.
How your truck handles the cool
It's the common misconception that you can't start your truck if the DEF is freezing. Luckily, that's not true. Your truck's computer knows exactly what the temperature is, and it's programmed to permit the engine to begin and run set up DEF tank is a solid block associated with ice.
The system uses a heating element—usually either an electric heater or a loop that runs motor coolant through the tank—to thaw the fluid. Once the particular engine gets up to operating temperature, that heat exchanges to the DEF. Within about twenty to 45 minutes of driving, the fluid starts to liquefy, and the SCR system begins operating as usual. A person won't get the warning light or go into sagging mode just because the fluid is frozen at startup; the EPA actually permits a "thaw period" before the emissions system is needed to be completely functional.
Storing your spare DEF jugs properly
A lot of guys like to keep an extra 2. 5-gallon jug within the bed from the truck or in a side tool box. While that's great for convenience, it's the recipe for a headache in January. If you're looking at how to keep DEF fluid from freezing that you haven't used yet, the answer is all about area.
If you can, keep your spare jugs within a climate-controlled area. In case you don't have the heated garage, even keeping them in a basement or a mudroom is much better than leaving all of them in the back again of the pickup truck. If you must store them in an unheated shed or garage area, try to keep them off the particular concrete floor. Cement acts like a giant heat sink and will stay chillier than the air around it. Putting your jugs on a wooden rack or a pallet can actually help slightly, though it won't stop all of them from freezing in case the air stays below 12 levels for days.
The biggest point to remember along with stored DEF is usually to check the particular jug for leakages after it thaws. Since the plastic material jugs are thin, that 7% development can sometimes generate micro-cracks. If you bring an iced jug into your home to thaw plus it has a crack, you're heading to have the very smelly, crystalline mess on your floor.
Never use additives or even "anti-freeze"
This is probably the most important piece of suggestions: never put anything into your own DEF tank to lower the freezing point.
I've heard stories associated with people trying to add a little bit of diesel fuel, rubbing alcohol, or even actual engine antifreeze to their DEF to keep it liquefied. This is the fast-track way to a $5, 500 repair bill. The particular SCR system is incredibly sensitive. The prompt inside your wear out is made associated with precious metals which are easily "poisoned" by foreign chemicals. Even a tiny amount of a different fluid can ruin the entire system, trigger the permanent limp mode, and void your warranty.
DEF is a quite specific mixture of high-purity urea and deionized water. Everything else you put in there—including tap water—will trigger mineral buildup plus mechanical failure. If this freezes, just let it freeze. The system is created to manage it.
Guidelines for the long-haul driver
If you're on the highway plus staying in resorts or sleeping in the cab, you may not possess the luxury of a warmed garage. In this particular case, the best choice is to just keep the particular truck running longer enough to keep the engine gulf and the chassis somewhat warm before you shut it lower for the night.
Several drivers use insulation wraps with regard to their DEF tanks. While these don't generate heat, these people can help support the heat gathered throughout a day of traveling. If you store your truck and the DEF is at 100 levels from the motor coolant heater, an insulated tank might stay above the freezing point for many hours longer than an exposed tank. It's not the perfect solution, but every little bit helps once the blowing wind chill is hitting double digits beneath zero.
What to do in case your DEF actually freezes
In case you walk out to your truck and realize the DEF is solid, don't panic. You don't need to consider a blowtorch to the tank (please, don't do that) or pour hot water over this.
The particular best thing you can do is simply start the pickup truck and drive it. The interior heaters will take care of the rest. If you're actually worried about it or if you're getting a "DEF system fault" because the lines are usually clogged with glaciers, the only genuine fix is warmth. If you can get the truck in to a warmed shop or even a garage for a several hours, that's usually enough to obtain things flowing once again.
An additional thing to watch out for is "white flakes" or even crystals around the particular cap. This happens when the water within the DEF evaporates plus leaves the urea behind. In the winter, this can get worse because the cold air is often very dried out. If you get a lot of white crusty buildup around your fill port, wipe it off with a damp material so it doesn't drop into the tank and create a blockage.
Does freezing ruin the DEF?
One issue that comes up the lot is regardless of whether DEF "goes bad" after it has been frozen and thawed. Thankfully, it doesn't. Unlike several chemicals that independent or break straight down if they change areas, DEF is totally fine once this turns back into a liquid. The urea doesn't drop out associated with suspension, as well as the concentration remains the same.
As long as the particular fluid hasn't been contaminated by dirt or other liquids, you can stop and thaw it as many times as the climate demands without dropping any effectiveness. All those things really kills DEF is heat plus sunlight—so keeping this cold in the particular winter actually helps preserve its rack life, even though this makes it a little harder to put!
Summary of best practices
Keeping your truck running smoothly in the winter doesn't have to be a chore. If you follow these basic steps, you'll most likely not have a problem with your DEF system:
- Don't fill this to the brim: Depart 20% of the particular tank empty with regard to expansion.
- Park indoors in case possible: Even an unheated garage is preferable to a windy driveway.
- Store free jugs inside: Keep them in the basements or a heated shop.
- Avoid additives: Stick to the pure stuff and let the truck's heater do its work.
- Be patient: Give the pickup truck time to warm up and thaw the particular lines before planning on the system to be fully functional.
Winter driving has enough challenges since it is. By understanding how to keep DEF fluid from freezing (or a minimum of how to manage it whenever it does), you can check a single more thing out of your list of cold-weather worries. Stay hot on the market!