Ever found yourself staring at the fuel gauge, miles from the nearest gas station, wondering if your Grand Cherokee has enough juice to make it? We’ve all been there. Whether you’re planning a long highway haul, a weekend camping trip, or tackling challenging trails, understanding your vehicle’s fuel capacity is crucial.
At FatBoysOffroad, we know that knowledge is power, especially when it comes to keeping your rig running smoothly. Today, we’re diving deep into the 2018 Jeep Grand Cherokee gas tank size, exploring not just the numbers, but how those figures translate into real-world range for your adventures.
This guide will equip you with the insights to plan your trips better, optimize your fuel efficiency, and ensure you’re never caught short on the road or the trail. We’ll cover everything from standard capacities to how driving conditions impact your range, and even discuss options for extending your fuel carrying capabilities.
Understanding the 2018 Jeep Grand Cherokee Gas Tank Size
The 2018 Jeep Grand Cherokee is a popular choice for its blend of rugged capability and daily comfort. When it comes to fuel capacity, most owners of the 2018 model year will find their vehicle equipped with a generous tank designed to provide a decent range.
Generally, the 2018 Jeep Grand Cherokee gas tank size is rated at 24.6 gallons (approximately 93.1 liters). This is a substantial capacity, especially when compared to many other SUVs on the market. This size is standard across most trim levels and engine configurations, offering a consistent baseline for fuel planning.
Standard Fuel Tank Capacity for Most Models
For the vast majority of 2018 Grand Cherokee owners, that 24.6-gallon tank is what you’ll be working with. This includes popular trims like the Laredo, Limited, Overland, Summit, and even the performance-oriented SRT and Trackhawk models, although their fuel consumption will vary wildly.
Knowing this exact figure is your first step in calculating potential range. It’s the foundation for all your fuel planning, whether you’re commuting or heading deep into the backcountry.
Engine Variations and Their Impact on Fuel Needs
While the physical gas tank size typically remains consistent across the 2018 lineup, the engine under the hood makes a huge difference in how far those 24.6 gallons will take you. Jeep offered several engine options for the 2018 Grand Cherokee, each with its own fuel economy characteristics.
- 3.6L Pentastar V6: This is the most common engine, offering a good balance of power and efficiency. It generally delivers the best fuel economy among the gasoline engines.
- 5.7L HEMI V8: A popular choice for those wanting more power and towing capability. This engine will naturally consume more fuel, reducing your overall range per tank.
- 6.4L SRT HEMI V8: Found in the Grand Cherokee SRT, this high-performance engine is a thirsty beast, designed for speed and power, not economy.
- 6.2L Supercharged HEMI V8: Exclusive to the Trackhawk, this supercharged powerhouse has the lowest fuel economy of the bunch, meaning more frequent stops at the pump.
- 3.0L EcoDiesel V6: This diesel engine, if you’re lucky enough to have one, offers significantly better fuel economy than its gasoline counterparts, extending your range considerably.
Always check your specific vehicle’s MPG ratings and factor them into your range calculations. A V6 owner will get far more miles out of their 2018 Jeep Grand Cherokee gas tank size than a Trackhawk owner.
Factors Affecting Your Real-World Range
The sticker MPG ratings are a good starting point, but they rarely tell the full story. Many variables influence how far you can actually travel on a full tank. Understanding these factors is key to accurate trip planning and avoiding unexpected fuel stops.
Driving Conditions: City vs. Highway vs. Off-Road
Your driving environment plays a massive role in fuel consumption.
City Driving: Frequent stops, starts, and idling burn more fuel. Expect lower MPG figures in urban environments.
Highway Driving: Steady speeds and minimal braking typically yield the best fuel economy. This is where your Grand Cherokee will likely achieve its advertised MPG.
Off-Road Driving: This is where things get interesting and challenging for your fuel budget. Low-range gearing, navigating obstacles, soft sand, mud, and steep climbs can drastically reduce your MPG. We’re talking single-digit figures in some extreme conditions.
When planning an off-road excursion, always assume your fuel consumption will be significantly higher than highway driving. It’s better to overestimate your needs and have extra fuel than to run dry in a remote area.
Engine Choice and Fuel Economy (MPG)
As mentioned, your engine is a primary determinant of fuel efficiency. Here’s a quick look at typical combined MPG estimates for the 2018 Grand Cherokee (actual results may vary):
- 3.6L Pentastar V6: Around 21 MPG combined (19 city/26 highway for 2WD, slightly less for 4WD).
- 5.7L HEMI V8: Around 17 MPG combined (14 city/22 highway).
- 6.4L SRT HEMI V8: Around 15 MPG combined (13 city/19 highway).
- 6.2L Supercharged HEMI V8 (Trackhawk): Around 13 MPG combined (11 city/17 highway).
- 3.0L EcoDiesel V6: Around 25 MPG combined (22 city/30 highway for 2WD, slightly less for 4WD).
Do the math: a 24.6-gallon tank with a 25 MPG diesel will take you over 600 miles, while a 13 MPG Trackhawk might only get you around 320 miles. That’s a huge difference in planning.
Tires, Lift Kits, and Cargo Weight
Modifications and cargo can significantly impact your fuel economy. Every off-roader knows the allure of bigger tires and a lifted stance, but these come at a cost to your MPG.
Larger, Aggressive Tires: Heavier, knobbier tires create more rolling resistance and require more power to turn, reducing fuel efficiency. The larger diameter also throws off your speedometer and odometer, making range calculations less accurate unless recalibrated.
Lift Kits: Raising your vehicle increases aerodynamic drag, especially at highway speeds. This added resistance means your engine works harder to maintain speed.
Roof Racks and Cargo: Any items on your roof rack, even an empty one, increase drag. Heavier loads inside the vehicle or towing a trailer also force the engine to consume more fuel.
Be honest with yourself about your modifications. If you’ve got a 3-inch lift and 33-inch mud-terrains, your actual MPG will be lower than the factory ratings. Factor this into your estimates when considering your 2018 Jeep Grand Cherokee gas tank size and its effective range.
Maximizing Your Fuel Efficiency and Range
Even with a good-sized fuel tank, every mile counts, especially when you’re far from civilization. Here are some actionable tips to squeeze every last drop of range out of your 2018 Grand Cherokee.
Maintenance for Better MPG
A well-maintained vehicle is a more efficient vehicle. Don’t overlook these basic steps:
Keep Tires Properly Inflated: Underinflated tires increase rolling resistance, forcing your engine to work harder. Check your tire pressure regularly, especially before long trips or off-road adventures. For off-roading, you might air down for traction, but remember to reinflate for highway travel.
Regular Oil Changes: Fresh, clean engine oil reduces friction within the engine, allowing it to operate more efficiently. Follow Jeep’s recommended oil change intervals and use the correct oil type.
Replace Air Filters: A clogged air filter restricts airflow to the engine, reducing its ability to combust fuel efficiently. A clean air filter is cheap and easy to replace.
Spark Plugs and Fuel System Cleanliness: Worn spark plugs or a dirty fuel system can lead to misfires and inefficient combustion. Regular maintenance, including fuel injector cleaning, helps maintain optimal performance and MPG.
Think of your Jeep as an athlete; it performs best when it’s in peak condition. Neglecting maintenance directly impacts your fuel economy.
Smart Driving Habits
How you drive has a monumental impact on your fuel consumption.
Smooth Acceleration and Braking: Aggressive driving – sudden starts and hard stops – wastes fuel. Accelerate gently and anticipate traffic to avoid unnecessary braking. Coasting to a stop is more efficient than slamming the brakes.
Maintain a Consistent Speed: Use cruise control on highways to maintain a steady speed. Varying your speed constantly requires more fuel.
Avoid Excessive Idling: If you’re going to be stopped for more than a minute, it’s often more fuel-efficient to turn off your engine and restart it when ready to go.
Limit High Speeds: Aerodynamic drag increases significantly with speed. Driving at 65 mph instead of 75 mph can noticeably improve your highway MPG.
Reduce Unnecessary Weight: Remove heavy items from your Jeep that you don’t need. Every extra pound your engine has to move requires more fuel.
These habits are not just good for your wallet; they’re also safer and reduce wear and tear on your vehicle.
Planning for Remote Expeditions
Off-roading and overland travel demand meticulous planning, especially concerning fuel. Your 2018 Jeep Grand Cherokee gas tank size alone might not be enough for truly remote areas.
Map Your Route and Fuel Stops: Before you leave, identify gas stations along your planned route, especially in wilderness areas. Use apps or physical maps to mark potential refueling points.
Calculate Your Estimated Range: Based on your known tank capacity and an honest assessment of your likely off-road MPG, calculate your realistic range. Always add a safety buffer (e.g., plan for 75-80% of your theoretical maximum range).
Consider Auxiliary Fuel: For truly remote or extended trips, carrying extra fuel is not just a good idea – it’s often essential. We’ll discuss options for this next.
Communicate Your Plans: If you’re heading into very remote areas, inform a friend or family member of your route and expected return time. This is critical for safety.
Never underestimate the harsh realities of running out of fuel far from help. A little planning goes a long way in preventing a bad situation.
Auxiliary Fuel Solutions for Extended Journeys
Sometimes, the 24.6-gallon 2018 Jeep Grand Cherokee gas tank size just isn’t enough. For serious overlanders or those exploring vast, uninhabited regions, auxiliary fuel solutions are a must.
Jerry Cans and Safe Storage
Jerry cans are the most common and accessible way to carry extra fuel. They are relatively inexpensive and can be found at most automotive or outdoor stores.
Choose Quality Cans: Invest in high-quality, robust metal or heavy-duty plastic fuel cans specifically designed for gasoline. Look for CARB-compliant (California Air Resources Board) or EPA-approved cans for safety and legality.
Secure Mounting: Never carry jerry cans loose inside your vehicle. Fumes are dangerous, and in an accident, a loose can becomes a projectile and a massive fire hazard. Use a dedicated jerry can mount on a roof rack, rear bumper swing-out, or exterior cargo carrier. Ensure it’s tightly secured to prevent rattling and damage.
Ventilation: Even properly sealed cans can emit fumes. Store them outside the passenger compartment. If you must carry them inside for a short period (e.g., after refueling), ensure maximum ventilation.
Filling and Handling: Always fill cans on the ground, not in your vehicle, to prevent static electricity buildup and potential fires. Wear gloves and eye protection. Fill to about 95% capacity to allow for expansion in heat.
Jerry cans are a simple solution, but they require careful handling and proper storage to ensure safety.
Aftermarket Auxiliary Tanks
For those who frequently undertake long-range expeditions, an aftermarket auxiliary fuel tank might be a worthwhile investment. These replace or supplement your factory tank, significantly increasing your overall fuel capacity.
Increased Capacity: Auxiliary tanks can add anywhere from 10 to 30+ gallons of extra fuel, effectively doubling your range. This is invaluable for remote travel.
Integrated Solution: Unlike jerry cans, an auxiliary tank is a permanent installation, often tucked away neatly under the vehicle or in a spare tire well. This keeps fuel out of the elements and frees up cargo space.
Professional Installation: Installing an auxiliary fuel tank is a complex job that typically involves modifying fuel lines, electrical systems, and potentially vehicle structure. It’s highly recommended to have a professional shop with experience in off-road modifications handle the installation to ensure safety and proper function.
Weight Distribution: Be mindful of the added weight, especially when the tank is full. This will impact your vehicle’s suspension, handling, and overall gross vehicle weight rating (GVWR). Consider upgrading your suspension if you plan to carry significant extra fuel and cargo.
While a bigger upfront investment, an auxiliary tank offers unmatched convenience and safety for serious adventurers looking to extend the capabilities of their 2018 Grand Cherokee.
Fuel Gauge Accuracy and When to Refuel
Your fuel gauge is a guide, not an absolute truth. It’s a common misconception that the “empty” light means you have no fuel left. Most vehicles, including the Grand Cherokee, have a reserve capacity after the low fuel warning illuminates.
However, relying on this reserve is a risky game, especially off-road. Fuel pumps in the tank rely on fuel to keep them cool. Running the tank repeatedly to near empty can shorten the life of your fuel pump. Additionally, off-road angles can temporarily expose the fuel pump pickup, leading to fuel starvation even if there’s still some fuel sloshing around.
As a rule of thumb, especially when adventuring, plan to refuel when your tank is around one-quarter full. This gives you a significant buffer for unexpected detours, trail closures, or simply longer-than-anticipated travel times. Don’t push your luck; finding fuel in the wilderness is not an option.
Safety Considerations When Handling Fuel
Fuel is highly flammable and needs to be treated with extreme caution. Safety should always be your top priority.
No Smoking or Open Flames: This seems obvious, but it’s worth repeating. Keep all ignition sources away from fuel.
Ventilate Area: Always work with fuel in a well-ventilated area to prevent the buildup of dangerous fumes.
Static Electricity: Static discharge can ignite fuel vapors. Always place fuel containers on the ground when filling. Touch a metal part of your vehicle before fueling to discharge any static from your body.
Spill Preparedness: Have rags or absorbent material on hand in case of spills. Know how to properly dispose of contaminated materials.
Fire Extinguisher: When carrying extra fuel, it’s wise to have an automotive-rated fire extinguisher easily accessible in your vehicle.
Children and Pets: Keep children and pets away from fuel and fueling operations.
These precautions are not just for your safety, but for the safety of everyone around you and the environment.
Frequently Asked Questions About the 2018 Jeep Grand Cherokee Gas Tank Size
What is the exact fuel tank capacity for a 2018 Jeep Grand Cherokee?
The standard fuel tank capacity for most 2018 Jeep Grand Cherokee models is 24.6 gallons (approximately 93.1 liters). This applies to most engine options and trim levels.
How many miles can a 2018 Grand Cherokee travel on a full tank?
The range varies significantly based on engine type and driving conditions. A 3.6L V6 model might achieve 500+ miles on the highway, while a 6.2L Trackhawk could be closer to 300-350 miles. Off-road driving will drastically reduce these figures.
Does the EcoDiesel have a different fuel tank size than gasoline models?
No, the 2018 Grand Cherokee EcoDiesel models typically use the same 24.6-gallon fuel tank as the gasoline versions. However, due to the diesel engine’s superior fuel economy, it will provide a much longer range on a single tank.
Can I put a larger gas tank in my 2018 Jeep Grand Cherokee?
Yes, aftermarket auxiliary fuel tanks are available that can replace or supplement your factory tank, significantly increasing your fuel carrying capacity. Professional installation is highly recommended for these modifications.
What type of fuel does the 2018 Jeep Grand Cherokee use?
Most gasoline models (V6, 5.7L V8) use regular unleaded gasoline (87 octane). The SRT and Trackhawk models require premium unleaded gasoline (91+ octane). The EcoDiesel model uses diesel fuel.
Hit the Trail with Confidence
Understanding your 2018 Jeep Grand Cherokee gas tank size and its real-world implications is more than just knowing a number; it’s about intelligent planning, safe adventuring, and maximizing the capabilities of your rig. Whether you’re a daily driver, a weekend warrior, or a serious overlander, taking the time to truly grasp your fuel situation will save you headaches, time, and potentially get you out of a sticky situation.
Keep your Grand Cherokee well-maintained, drive smart, and always plan your fuel stops, especially when heading off the beaten path. If your adventures take you far and wide, don’t hesitate to explore auxiliary fuel solutions to extend your range and peace of mind. Stay safe out there, and enjoy every mile of your journey!
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