2018 Jeep Grand Cherokee — Fluid Type Specs & Maintenance Guide

As an ASE-certified master technician, I’ve seen my fair share of vehicle issues caused by improper fluid top-offs. The WK2 generation Jeep Grand Cherokee, particularly the 2018 model year, is a remarkably capable and complex machine. With engine options ranging from the reliable 3.6L Pentastar V6 and torque-rich 3.0L EcoDiesel to the fire-breathing 6.2L supercharged Trackhawk V8, getting your fluids right is absolutely critical.

Whether you are performing your own preventative maintenance in the driveway or verifying what your local lube shop is pouring into your rig, this comprehensive fluid specification guide covers every factory-spec fluid required for the 2018 Jeep Grand Cherokee.

Quick reference

Note: Capacities are approximate dry-fill or service-fill estimates. Always verify fluid levels using the factory dipstick, overflow tank lines, or fill-plug weep holes. Refer to your owner’s manual for your specific engine and driveline combination.

Fluid	Type/Spec	Capacity
Engine Oil (3.6L V6)	0W-20 API SN/SP (Mopar MS-6395)	5.9 qt (5.6 L)
Engine Oil (5.7L V8)	5W-20 API SN/SP (Mopar MS-6395)	7.0 qt (6.6 L)
Engine Oil (6.4L & 6.2L V8)	0W-40 Full Synthetic (Mopar MS-12633)	7.0 - 7.5 qt (6.6 - 7.1 L)
Engine Oil (3.0L Diesel)	5W-40 Synthetic, API CJ-4/CK-4 (MS-10902)	8.2 qt (7.8 L)
Engine Coolant	Mopar 10-Year/150k OAT (Purple, MS-90032)	10.4 qt to 16.0 qt (varies)
Transmission Fluid	Mopar ZF 8 & 9 Speed ATF (MS-90030)	9.0 - 9.5 qt (total system)
Transfer Case (Standard)	Mopar ATF+4 (MS-9602)	2.0 qt (1.9 L)
Transfer Case (SRT/Trackhawk)	Mopar NV146 / BorgWarner Transfer Case Fluid	Verify in service manual
Front Differential	75W-85 GL-5 Synthetic (MS-9020)	~ 1.2 qt (1.1 L)
Rear Differential	75W-85 GL-5 Synthetic (MS-9020)	1.2 - 1.4 qt (1.1 - 1.3 L)
Brake Fluid	Mopar DOT 3 (MS-4574)	Fill to MAX line
Power Steering Fluid	EPS (No fluid) / Electro-Hydraulic (MS-11655)	Fill to MAX line
Washer Fluid	Standard All-Season Washer Solvent	Approx. 1 Gallon
DEF (3.0L Diesel Only)	Diesel Exhaust Fluid (ISO 22241)	~ 8.0 Gallons (30.3 L)

Engine Oil

For the 2018 Jeep Grand Cherokee, engine oil viscosity and specification vary wildly based on what’s under the hood.

• 3.6L Pentastar V6: Requires 0W-20 viscosity engine oil meeting Mopar MS-6395 and API SN/SP standards.
• 5.7L Hemi V8: Requires 5W-20 engine oil meeting Mopar MS-6395. Tech tip: Do not run heavier oils in the 5.7L, as the Multi-Displacement System (MDS) relies on the specific viscosity of 5W-20 to operate the hydraulic lifters correctly.
• 6.4L SRT and 6.2L Trackhawk: These high-performance engines require 0W-40 full synthetic oil meeting Mopar MS-12633. Pennzoil Ultra Platinum is the factory fill and highly recommended.
• 3.0L EcoDiesel: Requires 5W-40 full synthetic diesel engine oil meeting Mopar MS-10902 and API CJ-4 or CK-4 standards.

Interval: Most models feature an automatic Oil Life Indicator. However, do not exceed 10,000 miles or 12 months (whichever comes first). For harsh driving conditions, consider 5,000-mile intervals.

Engine Coolant

This is where I see the most catastrophic DIY mistakes. The 2018 Grand Cherokee requires Mopar 10-Year/150,000 Mile Formula OAT (Organic Additive Technology) coolant, which meets specification MS-90032. This fluid is distinctly purple.

Common Pitfall: Never mix this with the older Mopar HOAT (Hybrid Organic Additive Technology) coolant, which is orange/pink. Mixing OAT and HOAT creates a thick sludge that will clog your heater core and radiator, leading to thousands of dollars in cooling system repairs. Always use 50/50 premixed OAT or mix concentrated OAT with distilled water.

Transmission Fluid

All 2018 Grand Cherokees are equipped with variants of the ZF 8-speed automatic transmission (845RE, 8HP70, or 8HP95). The only acceptable fluid is Mopar ZF 8 & 9 Speed ATF (MS-90030) or an exact ZF LifeguardFluid 8 equivalent.

Common Pitfall: Never use universal ATF or ATF+4 in the ZF 8-speed. Doing so will severely degrade shift quality and destroy the transmission clutches. While Chrysler claims this is a "lifetime" fluid, ZF (the manufacturer of the transmission) recommends a fluid and filter/pan replacement every 50,000 to 75,000 miles depending on driving habits.

Transfer Case

If you have a 4WD model, your fluid depends on your transfer case system:

• Quadra-Trac I / Quadra-Trac II / Quadra-Drive II: Use Mopar ATF+4 (MS-9602).
• SRT / Trackhawk (Active On-Demand): High-performance models utilize a specific BorgWarner transfer case that requires heavily specialized fluid (Mopar NV146 or dedicated BorgWarner fluid). Never put ATF+4 in the SRT/Trackhawk transfer case.

Interval: Change the transfer case fluid every 30,000 to 60,000 miles.

Differentials (Front & Rear)

For both the front and rear axles, FCA calls for 75W-85 GL-5 Synthetic Gear Lubricant (MS-9020).

Common Pitfall (Limited Slip Additive): If your Grand Cherokee is equipped with Quadra-Drive II or the Electronic Limited Slip Differential (ELSD) in the rear, you must add Mopar Limited Slip Additive (Friction Modifier) to the gear oil to prevent the clutches from chattering on turns. If you purchase an aftermarket 75W-85 or 75W-90 gear oil that already states it contains limited-slip friction modifier, you generally do not need to add more.

Brake Fluid

The 2018 Grand Cherokee uses standard DOT 3 brake fluid (Mopar MS-4574).

Interval: Brake fluid is hygroscopic (absorbs moisture from the air). Flushing the brake fluid every 2 to 3 years is a highly recommended practice to prevent internal corrosion of ABS modules and brake calipers. Never substitute with DOT 5 (silicone-based) fluid.

Power Steering & Washer Fluid

• Power Steering: Most 2018 models (like the 3.6L and 5.7L) feature Electric Power Steering (EPS), meaning there is no fluid to check or leak. However, if you have a model with electro-hydraulic steering (common on the EcoDiesel, SRT, and Trackhawk), you must use Mopar Hydraulic System Power Steering Fluid (MS-11655). Do NOT use standard ATF+4 or conventional power steering fluid.
• Washer Fluid: Use any quality all-season windshield washer solvent. If you live in a cold climate, ensure it is rated for sub-freezing temperatures to avoid reservoir cracking.

Diesel Exhaust Fluid (DEF)

If you own the 3.0L EcoDiesel, you have a DEF tank. You must use Diesel Exhaust Fluid that meets ISO 22241 standards (API certified). The DEF tank holds approximately 8 gallons, and the cluster will alert you when you are running low. Keep it topped off, as running completely out of DEF will result in a no-start condition per federal emissions mandates.

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Proper fluid maintenance is the lifeblood of your Jeep. By following these factory specifications and intervals, you can ensure your Grand Cherokee provides reliable service for years to come. If you don't feel comfortable tackling these fluid flushes yourself, leave it to the professionals.

Find a trusted shop on Repairius.