Quick Facts:
- Covers: 3.6L Pentastar V6 trucks, model years 2020 to 2026.
- Engine oil: API-certified SAE 0W-20 meeting FCA MS-6395, 5 quarts with a filter.
- Coolant: Mopar 10 Year/150,000 Mile OAT coolant, MS.90032.
- Axles and transfer case: SAE 75W-85 GL-5 gear oil in both axles, Mopar ATF+4 in the transfer case. Amounts are unconfirmed.
- Best for: Gladiator owners who change their own fluids.
 9 min read
In This Guide
- Overview: Gladiator Fluid Capacities by System
- Gladiator Fluid Capacities Table
- Engine Oil Capacity and Type
- Coolant Capacity and Type
- Transmission and Transfer Case Fluid
- Front and Rear Axle Fluid
- Brake, Steering and Other Fluids
- Gladiator Fluid Service Intervals
- Final Thoughts
- Frequently Asked Questions
Overview: Gladiator Fluid Capacities by System
Gladiator fluid capacities, types and service intervals sit in different sections of the owner’s manual. I have owned five Jeeps, including a Gladiator, and I would rather have every fluid on one page.
The hard numbers here cover the 3.6L Pentastar V6 gas truck, model years 2020 to 2026. They come from the 2020 and 2026 owner’s manuals. The 3.0L EcoDiesel (2021 to 2023) gets a short note, because its manual pages are scanned images with no readable text. This guide does not verify the 2027 model year. For the 2027 truck, start with our 2027 Jeep Gladiator lineup article, then check the 2027 manual.
Gladiator Fluid Capacities Table
This table lists the fluid for each system on the 3.6L gas truck. The first row gives the Jeep Gladiator oil capacity and the Gladiator oil type.
| Fluid | Type | Capacity | Manual confirms |
|---|---|---|---|
| Engine oil with filter | API-certified SAE 0W-20, FCA MS-6395 | 5 qt | Yes |
| Coolant | Mopar 10 Year/150,000 Mile OAT, MS.90032 | 11.2 qt (2020 manual), 13.0 qt (2026 manual) | Yes |
| 8-speed automatic | Mopar ZF 8 & 9 Speed ATF | 9.5 qt dry fill | Type: yes. Amount: unconfirmed |
| 6-speed manual | Mopar ATF+4 | 4.76 pt | Type: yes. Amount: unconfirmed |
| Transfer case | Mopar ATF+4 | 3.38 pt (MP1622) or 3.72 pt (MP3022C) | Type: yes. Amount: unconfirmed |
| Front axle | Mopar 75W-85, API GL-5 | 2.18 pt | Type: yes. Amount: unconfirmed |
| Rear axle (M220) | Mopar 75W-85, API GL-5 | 3.06 pt (electronic locker), 2.87 pt (limited slip) | Type: yes. Amount: unconfirmed |
| Brake fluid | Mopar DOT 3, SAE J1703 | Not published | Type: yes. No capacity published |
| Fuel tank | 87 octane | 22 gal | Yes |
Every figure carries a label. “Confirmed” means the figure appears in the Mopar PDF for the 2020 Gladiator or the 2026 Gladiator. “Unconfirmed” means it comes from a typed copy of the manual’s spec table, with no matching Mopar document. Therefore, treat unconfirmed numbers as shopping estimates. Buy a little extra, and let the fill hole or the dipstick set the final amount.
Gladiator Fluid Shopping List
Use these bottle counts as a shopping list, since they round up the capacities above.
- Oil change: one 5-quart jug of 0W-20 meeting MS-6395, one filter and one spare quart.
- Front axle: 2 quarts of SAE 75W-85 GL-5 gear oil.
- Rear axle: 2 quarts of the same gear oil, plus limited slip additive for a Trac-Lok rear.
- Transfer case: 2 quarts of Mopar ATF+4.
- 6-speed manual transmission: 3 quarts of Mopar ATF+4.
- Coolant, only when due: about 3.3 gallons, matching the MS.90032 spec.
For the oil change, three products match the specs above. Valvoline Restore & Protect Full Synthetic 0W-20 Motor Oil comes in a 5-quart jug, and its listing names Chrysler MS-6395. It costs more per quart than some other jugs. Mopar’s Engine Oil Filter Kit (68191349AC) lists the Gladiator for 2021 to 2026, so confirm 2020 fitment before you order. A STEELMAN 24mm Low Profile Oil Filter Wrench Socket removes a 24mm filter cap. Measure yours first, because the listing does not name the Gladiator.
Gear for your Gladiator oil change
Valvoline Restore & Protect Full Synthetic 0W-20 Motor Oil 5 Quart …
Mopar Engine Oil Filter Kit (68191349AC) | OEM Car & Truck Replacem…
Engine Oil Capacity and Type
Safety note: First, park on level ground, set the parking brake and chock the wheels. Support the truck on jack stands rated for its weight, and never crawl under a truck held only by a jack. Hot oil scalds, so wait until the oil is warm, not hot. For coolant, wait until the engine is fully cold before you open the cap, because the system is under pressure. Keep used coolant away from pets, since it is toxic, and take used oil and coolant to an auto parts store for disposal.
The Jeep Gladiator oil capacity is 5 quarts with a filter change. According to the manual, use API-certified SAE 0W-20 oil meeting FCA specification MS-6395. Mopar 0W-20 full synthetic fits, and the 2026 manual says any equivalent oil must carry the API Starburst symbol. You also find the Gladiator oil type printed on the filler cap.
The manual publishes no oil capacity without a new filter. Also, it calls for a Mopar filter or an equivalent full-flow filter. Therefore, plan every change around a new filter and 5 quarts. Buy both together, and keep a spare quart for topping off.
Park on level ground, pour in 4 quarts, let the oil settle, check the dipstick, then add a little at a time. The 2020 manual says 1 quart raises the level from the bottom of the crosshatch to the top.
EcoDiesel Oil
The 3.0L EcoDiesel (2021 to 2023) uses a different oil. Unconfirmed figures list 5W-40 synthetic meeting FCA MS-12991 and 9 quarts with a filter. Confirm the figure in the 2023 owner’s manual for your truck. Specifically, check the printed page, because the online PDF is a scanned image.
Coolant Capacity and Type
Your Gladiator uses Mopar 10 Year/150,000 Mile Formula OAT coolant, specification MS.90032. It is an OAT coolant, not HOAT. The manual warns against mixing it with HOAT or “globally compatible” coolants. It also warns against propylene glycol and says to keep at least 50 percent coolant in the system.
Coolant capacity changed between manuals. The 2020 manual lists 11.2 quarts for the 3.6L. By 2026, the manual lists 13.0 quarts. Both figures include the recovery bottle filled to the MAX line, and neither manual explains the difference. Therefore, buy by the larger figure, about 3.3 gallons, and set the level at the MAX line when you finish. A drain and fill swaps only part of the system’s coolant, so expect some left over.
The manual calls for a flush and replacement at 10 years or 150,000 miles, whichever comes first. For cold-weather trips, see our guide to winterizing your rig. Our Gladiator EcoDiesel cooling problems article covers the heat issues of this engine.
Transmission and Transfer Case Fluid
The Gladiator transmission fluid for the 8-speed automatic is Mopar ZF 8 & 9 Speed ATF, or an equivalent. This transmission has no dipstick. The manual says the factory fill gives satisfactory lubrication for the life of the vehicle. It also says routine fluid and filter changes are unnecessary, unless contamination occurs or someone disassembles the unit.
The unconfirmed figure for the automatic is a dry fill of 9.5 quarts. Because the manual publishes no drain-and-fill amount, have a shop handle any service on this unit.
For the 6-speed manual, Gladiator transmission fluid is Mopar ATF+4, and the unconfirmed figure is 4.76 pints. The 2020 manual says the fluid level should sit between the bottom of the fill hole and a point no more than 3/16 inch below it.
Gladiator transfer case fluid is also Mopar ATF+4. Unconfirmed figures list two capacities, 3.38 pints for the MP1622 and 3.72 pints for the MP3022C. Check which transfer case your truck has before you buy fluid, using your build sheet or the tag on the case. The manual sets the fill level at the bottom edge of the fill hole, with the truck level. It calls for an inspection at 30,000, 90,000 and 150,000 miles.
Front and Rear Axle Fluid
Gladiator differential fluid is the same in the front axle and the M220 rear axle: Mopar Gear & Axle Lubricant, SAE 75W-85, API GL-5. The manual names the rear axle as the M220 (sales codes DRE and DRF) and gives no axle size for either end. A third-party copy labels both axles Model 44, so match parts by your axle tag and sales code. Front capacity is 2.18 pints (unconfirmed). For the rear, the same source lists 3.06 pints with the electronic locker and 2.87 pints with the limited slip, also unconfirmed.
A Trac-Lok limited-slip rear needs a friction modifier added to the gear oil. The unconfirmed figure is about 2.4 ounces of Mopar Limited Slip Additive. Skip it, and the clutches often chatter in turns. To learn how the electronic lockers work, read our locking differentials explained guide.
The 2020 manual also lists an M200 rear axle, which takes SAE 75W-140. By 2026, the manual lists only the M220. Check your axle tag before you buy gear oil.
Setting the Axle Fluid Level
The manual sets the axle level at about 1/8 inch below the bottom edge of the fill hole, with the truck level. It says to add lubricant only at the fill hole, and only up to this level. Remove the fill plug first, so a stuck plug does not leave you with a drained axle. Then drain the old fluid and pump new fluid in through the fill hole. Wait a few minutes, top off if the level drops, then refit the fill plug. Finally, tighten each plug to the torque in your service manual.
For the axle and transfer case service, three products fit the steps above. TRIAX DTF-2 Professional 75W-85 GL-5 Full Synthetic Differential & Drivetrain Fluid is a 75W-85 GL-5 gear oil, but it ships as a single quart, so plan on two bottles per axle. Its listing says Limited Slip Ready. The manual still calls for a friction modifier in Trac-Lok rears, so check with the seller before you skip the additive. Slippery Pete’s Fluid Pump for Standard Quart Bottles threads onto 28mm quart bottles. Thread fit is the main complaint in reviews, so test it on your bottle. Valvoline ATF 4 Full Synthetic Automatic Transmission Fluid is a licensed ATF+4 fluid rather than a Mopar-branded one, which matches the transfer case fluid type above.
Gear for your Gladiator axle and transfer case service
TRIAX DTF-2 Professional 75W-85 GL-5 Full Synthetic Differential & …
Valvoline ATF 4 Full Synthetic Automatic Transmission Fluid 1 Quart
Brake, Steering and Other Fluids
Buy DOT 3. Specifically, the manual calls for Mopar DOT 3 brake fluid, SAE J1703, and publishes no capacity. A third-party copy of the spec table also allows DOT 4 if DOT 3 is unavailable, but both manuals list DOT 3 only.
The Gladiator has electric power steering. However, the manual still lists a power steering reservoir for Mopar Electric Steering Pump Fluid, with no capacity. Fill the washer reservoir with windshield washer solvent only, never radiator antifreeze, and pick a freeze rating to match your climate. Fuel is 87 octane, and the tank holds 22 gallons. Finally, the A/C system uses R-1234yf refrigerant, so leave A/C service to a shop.
Gladiator Fluid Service Intervals
These intervals come from the 2020 and 2026 gas-engine schedules. First, the oil: change it when the oil change indicator calls for it. Never go past 10,000 miles, 12 months or 350 engine hours. In severe operating conditions, the 2020 manual says the message comes on as early as 3,500 miles after a reset. For dusty, off-road use or long idling, the 2020 manual also calls for a change at 4,000 miles. The 2026 text does not repeat these lines, but follow the shorter interval if you wheel your truck. Both schedules run on mileage or time, whichever comes first.
- Coolant: replace at 10 years or 150,000 miles, whichever comes first.
- Automatic transmission: no scheduled change under normal use.
- Manual transmission: no interval under normal use. For towing, off-road or heavy loads, change at 30,000 miles and every 30,000 after.
- Gladiator transfer case fluid: inspect at 30,000, 90,000 and 150,000 miles. Change at 60,000 and 120,000 miles only for police, taxi, fleet use or frequent trailer towing.
- Axles: inspect at 20,000, 60,000, 100,000 and 140,000 miles. Change at 40,000, 80,000 and 120,000 miles for police, taxi, fleet, off-road use or frequent towing. Under normal use the manual lists inspections only.
Off-road use also shortens the axle interval. After a rough trail day, check for leaks and weeping seals with our post trail inspection checklist.
Final Thoughts
The engine oil, coolant, ATF and gear oil specs in this guide come from the owner’s manual. Treat every unconfirmed capacity as a shopping estimate, and let the fill hole or the dipstick decide the real amount. Having owned a Gladiator, I would rather see you buy a little extra fluid than run short mid-job.
For a Saturday in the garage, change the oil with a new filter. Then check the axle and transfer case fluid at the listed mileage, and change it if you wheel the truck hard or tow. Skip the coolant until 10 years or 150,000 miles, and leave the automatic transmission to a shop.
Frequently Asked Questions
How much oil does a Jeep Gladiator take?
The 3.6L Gladiator takes 5 quarts of oil with a filter change, according to the 2020 and 2026 owner’s manuals. Per a third-party copy of the spec table, the 3.0L EcoDiesel takes 9 quarts.
What fluid goes in a Gladiator transfer case?
Mopar ATF+4 goes in the transfer case. Inspect it at 30,000, 90,000 and 150,000 miles, per the manual.
How much transmission fluid does a Gladiator 8-speed take?
A third-party copy lists a 9.5-quart dry fill. The manual says the factory fill lasts the life of the vehicle under normal conditions, and the unit has no dipstick, so ask a shop to service it.
What coolant does a Gladiator use?
It uses Mopar 10 Year/150,000 Mile OAT coolant, MS.90032. Capacity is 11.2 quarts in the 2020 manual and 13.0 quarts in the 2026 manual.
How often should you change Gladiator differential fluid?
The manual calls for an inspection at 20,000 miles and every 40,000 miles after. It calls for a change at 40,000, 80,000 and 120,000 miles for off-road use or frequent towing.