2020 Jeep Gladiator Fluid Specifications Guide

As an ASE-certified master technician, I’ve seen firsthand how using the wrong fluids can quickly turn a rugged off-roader into a very expensive driveway ornament. When the 2020 Jeep Gladiator hit the market, it brought the iconic Wrangler capability to a midsize truck platform. For its inaugural year, the Gladiator was exclusively powered by the 3.6L Pentastar V6. Keeping this powertrain, along with its heavy-duty axles and transfer case, running properly requires strict adherence to Stellantis (FCA/Mopar) fluid specifications.

Whether you are gearing up for a weekend rock-crawling expedition or just performing routine driveway maintenance, having the exact factory fluid specs is crucial. Below is the complete, factory-spec fluid guide for the 2020 Jeep Gladiator.

Quick Reference

Fluid	Type/Spec	Capacity
Engine Oil (3.6L V6)	0W-20 API SN/SP (Mopar MS-6395)	5.0 quarts (4.7L)
Engine Coolant	Mopar 10-Year/150k OAT (Purple) MS-90032	10.3 qts (Auto) / 11.2 qts (Manual)
Automatic Transmission	Mopar ZF 8&9 Speed ATF	~9.3 qts (Dry) - Verify in OEM info
Manual Transmission	Mopar Manual Trans Fluid (MS-9224)	2.1 quarts (2.0L)
Transfer Case	Mopar ATF+4 (MS-9602)	2.0 quarts (1.9L)
Front Differential	75W-85 API GL-5 Gear Oil	1.05 quarts (1.0L)
Rear Differential	75W-85 API GL-5 (Add friction modifier for LSD)	1.6 quarts (1.5L)
Brake Fluid	DOT 3 Brake Fluid (MS-4574)	Fill to MAX line
Power Steering	Mopar Electric Steering Pump Fluid (MS-11655)	Fill to MAX line
Washer Fluid	Standard All-Season Washer Solvent	Approx. 1 gallon
DEF (Diesel Exhaust)	N/A (EcoDiesel not available in 2020)	N/A

Note: Capacities are approximate and for dry-fill or general service reference. Always check the dipstick or fill-hole level to confirm proper fluid height.

Engine Oil

For the 2020 Jeep Gladiator’s 3.6L Pentastar V6, the manufacturer specifies 0W-20 engine oil that meets API SN or SP standards and the Mopar MS-6395 specification.

• Capacity: 5.0 quarts with a new oil filter.
• Intervals: The Gladiator is equipped with an Automatic Oil Change Indicator System. Under normal driving, you should change the oil when the light comes on (never exceed 10,000 miles or 12 months). If you frequently tow, off-road, or idle for extended periods, I highly recommend a shorter 5,000-mile interval.
• Pitfalls: Don't substitute heavier weight oils like 5W-30 thinking it will protect better; the variable valve timing (VVT) solenoids on the Pentastar engine rely on the precise flow characteristics of 0W-20 to function properly.

Engine Coolant

FCA (Stellantis) cooling systems are notoriously sensitive to the wrong coolant. The 2020 Gladiator requires Mopar 10-Year/150,000 Mile Formula OAT (Organic Additive Technology), which meets spec MS-90032.

• Color: Factory OAT is typically purple.
• Pitfalls: Never mix OAT with HOAT (Hybrid Organic Additive Technology). Older Chrysler vehicles used an orange/pink HOAT coolant. If you mix HOAT into your Gladiator’s OAT system, it can cause the coolant to gel, leading to catastrophic heater core clogging and engine overheating. Never use "universal" green coolants either.

Transmission Fluid

The 2020 Gladiator was offered with two excellent transmissions, but their fluid requirements are vastly different:

• 8-Speed Automatic (850RE): Requires Mopar ZF 8&9 Speed ATF. This transmission is technically a "fill for life" unit under normal conditions, but heavy towers and off-roaders should service it every 60,000 miles. Never use ATF+4 or universal ATF in the ZF 8-speed. Doing so will destroy the delicate clutch packs.
• 6-Speed Manual (Aisin AL6): Requires Mopar Manual Transmission Fluid meeting spec MS-9224. Standard service intervals apply—check your owner’s manual, but generally replace every 30,000 to 40,000 miles under severe duty.

Transfer Case

The Gladiator uses either the Command-Trac (Sport/Overland) or Rock-Trac (Rubicon) transfer case. Both require Mopar ATF+4 meeting spec MS-9602.

• Intervals: Check the fluid every 30,000 miles, but replace it at 60,000 miles, or more frequently (every 30k) if you frequently submerge the axles and transfer case during water crossings or perform heavy towing.

Front and Rear Differentials

The Gladiator boasts heavy-duty Dana 44 axles front and rear (M210 front, M220 rear). Both differentials require 75W-85 API GL-5 gear oil.

• LSD Additive Note: If your Gladiator is equipped with the Trac-Lok anti-spin (Limited Slip) rear differential, you must use a friction modifier additive. Most premium synthetic gear oils include this, but verify on the bottle. Rubicon models with electronic lockers do not require friction modifier.
• Intervals: Inspect every 20,000 miles. If you frequently drive through deep water or mud, inspect the fluid immediately afterward. If it looks milky, water has entered through the breather tube, and the fluid must be changed immediately to prevent gear pitting.

Brake and Power Steering Fluids

• Brake Fluid: Use DOT 3 brake fluid meeting SAE J1703 or Mopar MS-4574. Do not use DOT 5 (silicone-based) fluid, as it is incompatible with the ABS system. Bleed and flush the brake system every 2 to 3 years to prevent moisture buildup, which can corrode internal ABS valving.
• Power Steering: The Gladiator uses an Electro-Hydraulic Power Steering (EHPS) pump. It requires Mopar Electric Steering Pump Fluid (Spec MS-11655). Standard ATF+4 is not an acceptable substitute for this advanced EHPS system.

Washer Fluid and DEF

• Washer Fluid: Use any standard automotive washer fluid. In freezing climates, ensure it is rated for at least -20°F to prevent the reservoir and lines from cracking.
• DEF: The 2020 Jeep Gladiator was only offered with the 3.6L gasoline engine. The 3.0L EcoDiesel was not introduced until the 2021 model year, so there is no Diesel Exhaust Fluid (DEF) required for 2020 models.

Taking care of your Jeep Gladiator with exact, factory-spec fluids is the best way to ensure it survives everything from the daily commute to the Rubicon Trail. If you aren't comfortable performing these services yourself, don't leave it to a quick-lube shop that might use the wrong universal fluids. Find a trusted shop on Repairius.