Does Ram Ecodiesel Use Def?

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The Ram Ecodiesel is equipped with an advanced emissions control system that requires diesel exhaust fluid (DEF) for proper operation. DEF is essential for reducing harmful nitrogen oxide (NOx) emissions from the diesel engine’s exhaust. So the short answer is – yes, the Ram Ecodiesel does use DEF.

What is DEF and Why is it Needed?

DEF is a liquid solution composed of urea and deionized water. It is injected into the exhaust stream of diesel vehicles like the Ram Ecodiesel to enable a process called selective catalytic reduction (SCR). SCR uses the DEF solution to convert NOx emissions into harmless nitrogen gas and water vapor.

NOx gases contribute to air pollution and smog formation. They are also linked to adverse health effects. Diesel vehicles tend to produce higher NOx emissions compared to gasoline vehicles. To meet stringent emissions regulations, diesel engines rely on SCR systems and DEF to curb NOx output.

Without DEF, the SCR system would be ineffective at reducing NOx. This would lead to excess emissions, emission control malfunctions, and reduced engine performance in the Ram Ecodiesel. So DEF is an essential fluid that must be periodically refilled.

How Does the DEF System Work?

Here is a quick overview of how the DEF system functions in the Ram Ecodiesel:

  • The DEF solution is stored in a tank and injected into the exhaust upstream of a catalyst.
  • When the hot exhaust gases mix with DEF, the urea breaks down into ammonia.
  • The ammonia reacts with NOx on the SCR catalyst surface and converts the harmful gases into nitrogen and water vapor.
  • This reaction lowers tailpipe NOx emissions to acceptable levels.
  • Sensors monitor NOx levels and regulate DEF dosage to ensure optimal emissions reduction.
  • The DEF tank needs to be refilled when low to keep the system functioning.

DEF Consumption in the Ram Ecodiesel

DEF consumption in the Ram Ecodiesel depends on driving conditions and habits. Aggressive driving with heavy engine loads will use more DEF compared to light-load driving. The EPA estimates the DEF refill interval to be approximately:

  • 5,000-6,000 miles for the 1/2 ton Ram 1500 Ecodiesel
  • 10,000-12,000 miles for the 3/4 and 1 ton Ram 2500/3500 Ecodiesels

However, actual DEF refill intervals can vary significantly based on driving behavior. Towing heavy loads, frequent city driving, and excessive idling can all increase DEF usage. Maintaining consistent driving habits is important to predict DEF refill needs.

The DEF tank capacity is also a factor. Here are the tank sizes for different Ram Ecodiesel models:

  • Ram 1500: 5 gallons
  • Ram 2500: 5-6 gallons
  • Ram 3500: 10 gallons

A larger tank means less frequent refilling. The Ram 3500 HD with its 10 gallon capacity can potentially go 20,000+ miles between DEF refills with light-duty driving.

Maintaining the DEF System

To keep the DEF system functioning properly in a Ram Ecodiesel, the following maintenance is recommended:

  • Use reputable DEF: Purchase DEF that meets ISO 22241 standards to ensure optimal quality. Many manufacturers offer DEF under various brand names.
  • Prevent contamination: Use properly labeled DEF-only containers to refill the tank. Contaminants like diesel fuel can clog components.
  • Check DEF level regularly: Monitor the DEF gauge and refill when the tank is around 1/4 full. Running out of DEF can cause the vehicle to enter a limited operating mode.
  • Refill at oil changes: Tying DEF refills to regular oil changes every 5,000-10,000 miles helps maintain supply.
  • Address warning lights: DEF system warning lights should not be ignored. Have the dealer diagnose any faults promptly.

Proper DEF filling and system maintenance will keep the Ram Ecodiesel’s SCR emission controls working effectively for years.

DEF Quality Standards

The DEF used in the Ram Ecodiesel must meet the ISO 22241 standard. This specification defines the allowable composition limits and purity for DEF solutions:

  • Urea content between 31.8-33.2%
  • Water meeting high purity deionized standards
  • Very low levels of contaminants like metal ions, alkalinity, and biuret

DEF that meets ISO 22241 is tested thoroughly and will not corrode system components or form deposits. Lower quality fluids can damage sensitive parts like injectors and valves over time.

The API (American Petroleum Institute) also certifies DEF solutions that satisfy the ISO 22241 criteria. Look for API certification when purchasing DEF. Reputable brands found at most auto parts stores and fueling stations will carry API-approved or ISO-compliant DEF.

Consequences of Running Out of DEF

It is important not to deplete the DEF supply in the Ram Ecodiesel. Running out of DEF can lead to:

  • Excess NOx emissions exceeding limits
  • Activation of dashboard warning lights and engine derate system
  • Reduced engine power in limp-home mode to enforce refilling
  • Inability to restart the engine once stopped without DEF

When the DEF gauge reaches a low level, it is critical to refill soon. Precautions like keeping extra DEF containers as backup can prevent being stranded without DEF.

Ignoring low DEF warnings may cause the vehicle to eventually enter an operating limit of only 5 mph once stopped. This forces the driver to replenish the empty DEF tank before full engine power is restored.

Finding DEF Refill Stations

DEF is becoming more widely available with the growth in SCR-equipped diesel vehicles. There are several ways to find DEF when refilling:

  • At the diesel pump at fueling stations – look for the blue DEF handle.
  • In packaged containers at auto parts stores, Walmart, truck stops, etc.
  • Specialized DEF filling pumps at some truck stops.
  • Fleet vehicle facilities with DEF dispensing systems.
  • Search for DEF locations using apps like Diesel Exhaust Fluid Locator.

DEF is commonly priced per gallon similar to diesel fuel. Buying packaged DEF in 2-2.5 gallon jugs is convenient for DIY refilling. Overall, DEF is a small additional operating cost for the emissions benefits it provides.

The Takeaway on Ram Ecodiesel and DEF

To summarize, the Ram Ecodiesel does rely on DEF in conjunction with its SCR system to lower NOx emissions to an acceptable level. Proper DEF usage keeps the vehicle operating in compliance with emissions regulations.

Monitoring DEF levels and refilling regularly every 5,000-10,000 miles is recommended. Using high-quality ISO-compliant DEF prevents any complications with the emissions control system. Overall, the benefits of cleaner tailpipe emissions outweigh the minor inconvenience of periodic DEF refilling.

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