2020 Jeep Wrangler Coolant Capacity, Type, and Refill Guide

The 2020 Jeep Wrangler holds between 9.2 and 13.0 quarts of coolant, depending on which engine option and transmission your vehicle is equipped with. As an ASE-certified master technician, I often see modern Jeep Wranglers (the JL generation) roll into the shop with cooling system confusion. Using the wrong coolant in these advanced engines can lead to catastrophic failure, gelling, or severe heater core blockages. Here is your definitive guide to the 2020 Jeep Wrangler’s cooling system.

Quick Answer

Before you top off your reservoir or start a full system flush, here are the essential specifications you need to know:

• Total cooling system capacity: 9.2 to 13.0 quarts (8.7 to 12.3 liters), depending on the engine.
• OEM coolant spec: Mopar 10-Year/150,000 Mile OAT (Organic Additive Technology). The Chrysler specification number is MS-12106 or MS-90032. This factory coolant is purple in color. Caution: Under certain lighting, it can appear pink or orange, but it is strictly an OAT formula. Never mix this with the older Chrysler HOAT (orange/pink) coolant used prior to 2013.
• Mix ratio: 50/50 mixture. You can purchase this pre-mixed, or buy concentrate and mix it 50% with distilled water (never tap water).

Capacity by Engine Option

The 2020 Wrangler offers several powertrains, each with its own cooling demands. The capacities below represent a dry fill (a completely empty system). Note that simple drain-and-fills will require less coolant, as some old fluid remains in the engine block and heater core.

Note: The 2.0L Turbo also features a separate, smaller cooling circuit for the charge air cooler (intercooler) and motor generator unit on eTorque models, which has its own capacity of roughly 3 to 4 quarts.

Flush Interval

• Normal Duty: Mopar specifies a flush interval of 10 years or 150,000 miles, whichever comes first.
• Severe Duty: If you frequently off-road, tow, idle for extended periods, or drive in extreme heat or dusty conditions, I highly recommend flushing the system every 5 years or 75,000 miles. Dirt and degraded coolant inhibitors can quickly destroy a water pump.

How to Refill & Bleed

The 2020 Wrangler cooling system is notorious for trapping air pockets, particularly the 3.6L Pentastar. Air in the system can cause overheating and a lack of heat in the cabin.

1. Drain: Open the petcock on the passenger side lower corner of the radiator.
2. Vacuum Fill (Recommended): The absolute best way to fill a JL Wrangler is by using a vacuum coolant filling tool hooked up to an air compressor. This draws the system into a vacuum and sucks the new coolant in, eliminating 99% of air pockets automatically.
3. Manual Fill & Bleed: If you are filling manually, slowly pour the 50/50 mix into the radiator. On the 3.6L V6, locate the bleeder screw on top of the thermostat housing. Open it slightly while filling until a steady stream of coolant (without bubbles) flows out, then tighten it.
4. Burping: Leave the radiator cap off (or use a spill-free funnel). Start the engine and turn the cabin heater to maximum heat and blower. Let the Jeep reach operating temperature so the thermostat opens. Add coolant as the level drops and bubbles escape.
5. Final Check: Cap the system, drive it, let it cool down completely, and check the reservoir. Top off the reservoir to the MAX line.

Common Cooling System Issues

For the JL generation, keep an eye out for these frequent cooling system problems:

• Oil Filter Housing/Cooler Leak (3.6L V6): The plastic oil cooler assembly sits in the valley of the V6 engine. Over time, the O-rings harden, causing oil and coolant to pool in the engine valley and run down the back of the transmission.
• Radiator Seam Leaks: The factory radiators are composed of an aluminum core crimped to plastic end tanks. These crimps are prone to weeping coolant, usually noticeable by a sweet smell and a purple crust forming on the sides of the radiator.
• Water Pump Weepage: The 3.6L water pump bearings can develop play, leading to a slow coolant weep from the weep hole behind the pulley.

Keeping your coolant fresh and filled to the proper level is the best way to keep your Jeep out on the trail and out of the service bay.

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