How to Change Transmission Fluid & Filter on a 2018 Jeep Grand Cherokee (8-Speed)
Step-by-step drain, pan/filter replacement, and temperature-based refill with tools, parts, and torque specs
How to Change Transmission Fluid & Filter on a 2018 Jeep Grand Cherokee (8-Speed)
Step-by-step drain, pan/filter replacement, and temperature-based refill with tools, parts, and torque specs


š§ Grand Cherokee - Transmission Fluid & Filter Service
On your Grand Cherokee, a proper transmission āfluid changeā is really a drain + pan/filter replacement + temperature-based refill. The fluid level is set through a fill plug while monitoring transmission temperature, so doing it the right way prevents slipping, harsh shifts, or damage.
Difficulty Level: Advanced | Estimated Time: 2.0-4.0 hours
ā ļø Safety & Precautions
- ā ļø Work on a level surface; support with jack stands before going underneath.
- ā ļø Transmission fluid can be hot; let it cool and wear gloves/eye protection.
- ā ļø The fill-level check is done with the engine runningākeep hands/clothes clear of rotating parts.
- ā ļø The vehicle must be level when setting the fluid level, or the fill will be wrong.
š§ Required Tools
You'll need the following tools for this repair:
- Floor jack (rated 3-ton minimum)
- Jack stands (rated 3-ton minimum)
- Wheel chocks
- Nitrile gloves
- Safety glasses
- Drain pan (10-quart minimum)
- Torx T40 bit socket
- Torx T50 bit socket
- 8mm hex bit socket
- 3/8" drive ratchet
- 6" extension (3/8" drive)
- Torque wrench (in-lb/ft-lb capable)
- Trim clip tool
- Brake cleaner
- Plastic scraper
- Fluid transfer pump (specialty)
- OBD2 scan tool with transmission temperature PID (specialty)
š© Required Parts
HowToo sells all the parts you need for this repair:
- Automatic transmission pan with integrated filter - Qty: 1
- Transmission pan bolts - Qty: 1 set
- Transmission drain plug seal - Qty: 1
- Transmission fill plug seal - Qty: 1
- 8-speed automatic transmission fluid (Mopar 8&9 Speed ATF equivalent) - Qty: 7-9 quarts
š Before You Begin
- Park your Grand Cherokee on a level surface and chock the wheels.
- Raise and support it so it sits level on jack stands (not nose-up).
- Plan to monitor transmission temperature with an OBD2 scan tool (it reads live data from the vehicle).
- Quick check (please confirm): Is your transmission pan black plastic with an integrated filter? If itās a metal pan with a separate filter, tell me before you start so I can switch you to the correct procedure.
šØ Step-by-Step Instructions
Follow these steps in order:
Step 1: Warm the transmission slightly
- Use your OBD2 scan tool with transmission temperature PID (specialty) to view transmission fluid temperature.
- Start the engine and let it idle until the transmission is roughly warm (not hot). Warm drains faster and cleaner.
- Shut the engine off before draining.
Step 2: Remove the underbody shield (if equipped)
- Use a trim clip tool to pop any plastic retainers.
- Use a 3/8" drive ratchet with the correct bit/socket to remove any shield fasteners you can access.
- Set the shield aside so you can reach the transmission pan and plugs.
Step 3: Loosen the fill plug first (important)
- Place the drain pan (10-quart minimum) under the transmission area.
- Use an 8mm hex bit socket with a 3/8" drive ratchet to crack the fill plug loose (do not remove it yet).
- If the fill plug wonāt budge, stop hereādonāt drain it if you canāt refill it.
Step 4: Drain the old fluid
- Use a Torx T50 bit socket with a 3/8" drive ratchet to remove the drain plug.
- Let the fluid drain until it slows to a drip.
- Clean the drain plug and install a new drain plug seal.
- Reinstall the drain plug and Torque to 35 Nm (26 ft-lbs).
Step 5: Remove the transmission pan/filter assembly
- Keep the drain pan (10-quart minimum) under the panāmore fluid will come out.
- Use a Torx T40 bit socket with a 3/8" drive ratchet and 6" extension to remove the pan bolts.
- Support the pan with one hand as you remove the last bolts, then lower it carefully.
- Use brake cleaner and a plastic scraper to clean the mating surface on the transmission case (no gouging).
Step 6: Install the new pan/filter assembly
- Position the new pan/filter up to the transmission.
- Hand-start all pan bolts to avoid cross-threading.
- Use a torque wrench to tighten pan bolts evenly in a crisscross pattern: Torque to 8 Nm (71 in-lbs).
Step 7: Initial refill (engine OFF)
- Remove the fill plug fully using the 8mm hex bit socket.
- Use a fluid transfer pump (specialty) to pump in 8-speed automatic transmission fluid until it begins to run back out of the fill port.
- Install the fill plug finger-tight for now (youāll reopen it for final level set).
Step 8: Final fluid level set (engine RUNNING, temperature-based)
- Start the engine. Keep your foot on the brake.
- Use the OBD2 scan tool with transmission temperature PID (specialty) to monitor transmission temperature.
- Move the shifter slowly through all gears (P-R-N-D and back), pausing 2ā3 seconds in each, then leave it in PARK.
- With the engine idling, remove the fill plug using the 8mm hex bit socket.
- Use the fluid transfer pump (specialty) to add fluid until it dribbles out in a thin stream.
- Set the level at the proper temperature window: 30ā50°C (86ā122°F). If itās below, it may underflow; if itās above, it may overflow and end up low after cooling.
- When the fluid is a light dribble at the correct temp, install a new fill plug seal, reinstall the fill plug, and Torque to 35 Nm (26 ft-lbs).
Step 9: Reinstall shields and clean up
- Use a trim clip tool to reinstall retainers for the underbody shield.
- Use brake cleaner to clean any spilled fluid so leaks are easy to spot later.
ā After Repair
- Test drive gently for 10ā15 minutes and confirm shifts feel normal.
- Park on a clean surface and check for drips under the transmission.
- If you have any delayed engagement, slipping, or flare on shifts, re-check the level at 30ā50°C (86ā122°F) using the same procedure.
š° DIY vs Shop Cost
Shop Cost: $450-$900 (parts + labor)
DIY Cost: $160-$350 (parts only)
You Save: $290-$550 by doing it yourself!
Shop labor rates vary but typically run $100-$150/hour. This repair takes a shop approximately 2-4 hours.
šÆ Ready to get started?
HowToo makes it easy: same-day/2-day shipping on every part, plus all the tools and specialty tools you need! Check out the parts and tools sections below to add everything to your cart.

















