If you drive a 2018 Jeep Compass, keeping your engine cool is crucial for performance and safety. The coolant you choose isn’t just about topping off a reservoir it affects your engine’s life and efficiency.
Many drivers overlook the details and risk costly repairs later.
If you want to make the right choice, you’ll need to understand which coolant fits your Compass, how to spot the right product, and what mistakes to avoid.
Why Coolant Choice Matters
The coolant does more than keep your engine from overheating. It also prevents corrosion, lubricates moving parts, and helps maintain a stable temperature even in extreme weather. Using the wrong coolant can cause engine damage, leaks, or failed parts. In recent years, automakers have moved away from generic green coolant to advanced formulas that match modern engines’ needs.
For the 2018 Jeep Compass, following manufacturer guidelines is key. Jeep designed your vehicle to work with a specific coolant chemistry.
Using something else may seem harmless, but it can invalidate warranties or cause damage over time.
The Right Coolant For 2018 Jeep Compass
The 2018 Jeep Compass requires OAT coolant (Organic Acid Technology). Jeep and FCA (Fiat Chrysler Automobiles) recommend using Mopar Antifreeze/Coolant 10 Year/150,000 Mile Formula OAT (Part Number 68163848AB or equivalent).
This coolant is usually purple in color, though sometimes it may appear pink depending on the batch or lighting. Never mix it with green or orange coolants, as chemical reactions can reduce protection or form sludge.
Key Specifications
- Type: OAT (Organic Acid Technology)
- Color: Purple (sometimes pinkish)
- Part Number: Mopar 68163848AB (or equivalent OAT meeting FCA MS-12106)
- Interval: Replace every 10 years or 150,000 miles, whichever comes first
Always check your owner’s manual for confirmation. Some Compass models made for other regions may have slight variations, so double-check if your vehicle was imported.
How Oat Coolant Differs From Others
OAT coolants use organic acids instead of silicates or phosphates to prevent corrosion. This gives them a longer life and better protection for modern aluminum engines. Traditional green coolants (IAT) or older orange coolants (HOAT) do not provide the same benefits and may actually cause corrosion if mixed with OAT.
Here’s a quick comparison of coolant types:
| Coolant Type | Typical Color | Change Interval | Compatibility with 2018 Compass |
|---|---|---|---|
| OAT | Purple/Pink | 10 years/150,000 miles | Yes |
| HOAT | Orange/Yellow | 5 years/100,000 miles | No |
| IAT | Green | 2 years/30,000 miles | No |
How To Check And Add Coolant
- Wait for the engine to cool before opening the coolant reservoir cap.
- Locate the coolant tank under the hood (usually on the passenger side).
- Check the fluid level against the “MIN” and “MAX” marks.
- If low, add Mopar OAT coolant premixed with distilled water in a 50/50 ratio.
- Replace the cap securely.
Never mix different coolant types, and avoid topping off with water alone unless it’s an emergency.
Mistakes To Avoid
Many owners accidentally mix coolants, thinking any “universal” product will do. This can lead to sludge formation or cooling system clogs. Others may use tap water, which introduces minerals that cause scaling and corrosion. Always use distilled water if you need to dilute concentrate.
Another common mistake is skipping coolant change intervals. OAT coolant lasts longer, but not forever.
Old coolant loses its anti-corrosion properties and can even turn acidic, eating away at engine parts.
Signs You Need To Change Coolant
Don’t just rely on mileage or years. Watch for these signs:
- Rusty or brown coolant
- Floating debris in the reservoir
- Low fluid level despite no visible leaks
- Engine runs hotter than normal
If you notice these, flush the system and refill with fresh Mopar OAT coolant.
How To Choose The Best Coolant Brand
While Mopar is the official brand, several reputable aftermarket brands offer OAT coolant compatible with FCA MS-12106. Look for:
- Certification: Must state FCA MS-12106 approval
- Pre-mixed or concentrate: Pre-mixed is easier and safer for most drivers
- Reputable sources: Buy from trusted auto parts stores or dealers
Here’s a comparison of popular brands:
| Brand | OAT Approval | Pre-mixed Option | Price Range (per gallon) |
|---|---|---|---|
| Mopar | Yes (MS-12106) | Yes | $20-$30 |
| Peak OET | Yes (FCA OAT) | Yes | $18-$25 |
| Zerex | Yes (OAT European Vehicle) | Yes | $15-$22 |
Some online guides suggest universal coolants, but these are rarely a safe bet for FCA vehicles. Always check compatibility on the label.
Advanced Tips Most Drivers Miss
- Flush the cooling system every time you change coolant. Old coolant can contaminate new fluid.
- If you live in very cold or very hot climates, check the freeze and boil protection on the bottle. OAT coolants typically protect to -34°F and up to 265°F when properly mixed.
- If you’re unsure about a product, consult your local Jeep dealer or check the official Jeep website.
For more technical details, visit the official Jeep Owner’s Manual page.
Frequently Asked Questions
What Color Coolant Does A 2018 Jeep Compass Use?
The 2018 Jeep Compass uses purple OAT coolant. Some brands may appear slightly pink, but it should never be green or orange.
Can I Mix Different Coolants In My 2018 Compass?
No. Mixing coolants can cause chemical reactions, leading to sludge and poor cooling. Always use OAT coolant approved for FCA vehicles.
How Often Should I Change The Coolant?
Change the coolant every 10 years or 150,000 miles, whichever comes first. Replace sooner if you see signs of contamination or overheating.
What Happens If I Use The Wrong Coolant?
Using the wrong coolant can cause corrosion, leaks, and overheating. It may also void your warranty and lead to expensive repairs.
Can I Use Water Instead Of Coolant In An Emergency?
In a true emergency, you can use distilled water to reach a safe location, but replace it with the correct coolant as soon as possible. Never use tap water, as it can damage your cooling system.
Choosing the right coolant for your 2018 Jeep Compass isn’t complicated, but it’s important to get it right. Stick with Mopar OAT or a certified equivalent, follow your maintenance schedule, and your Compass will run smoothly for years to come.
