2018 Dodge Durango Transmission Fluid Change Guide — Step-by-Step

The 2018 Dodge Durango pairs with the ZF 8HP70 8-speed automatic transmission — a genuinely excellent transmission that earned its reputation for smooth, intelligent shifting. The 8HP70 is robust, but like any transmission, it depends on clean fluid to protect its clutch packs, solenoids, and torque converter.

The job that trips up Durango owners: this transmission has no traditional drain plug on the pan. The fluid is changed using the fill tube method — drain via a drain plug on the torque converter housing, fill via a dipstick tube or fill plug.

Transmission: ZF 8HP70

• Required fluid: Mopar ATF+4 (Part #68218925AA or ZF Lifeguard 8 equivalent)
• ATF+4 only — this is not negotiable. The 8HP70's clutch pack friction material and solenoid tolerances are calibrated for ATF+4's specific additive package. Dexron, Type F, or generic ATF will cause shudder, improper shift timing, and accelerated wear.
• Capacity (drain-and-fill): Approximately 4–5 quarts (partial, without pan drop)
• Full pan drop capacity: ~9 quarts total
• Service interval: Every 30,000–45,000 miles for longevity (despite Mopar's extended recommendation)

Locating the Drain Plug

On the 8HP70, there is a small drain plug on the bottom of the transmission case — not on the pan itself. It's typically a 5/8" hex plug. Look slightly above and forward of the pan's lowest edge on the torque converter housing area.

Locating the Fill Point

The 8HP70 in the Durango has two configurations:

1. Dipstick tube: Some trims have a red-handled dipstick tube accessible from the engine bay. Fill fluid here.
2. Fill plug on the side of the case: A 17mm hex plug on the driver's side of the transmission case. Fluid is filled until it runs out of the hole at operating temperature.

Check your specific Durango before starting — pop the hood and look for a red dipstick handle near the back of the engine.

Step-by-Step: Drain-and-Fill

Preparation:

1. Drive the Durango for 10–15 minutes to bring the transmission to operating temperature. Warm fluid drains more completely.
2. Lift the car on ramps or jackstands.

Drain: 3. Position your drain pan under the drain plug location. 4. Remove the drain plug — use a 5/8" socket on a 1/2" drive ratchet. 5. Let the fluid drain completely — 3–5 minutes. Approximately 4–5 quarts will drain. 6. Inspect the drain plug — clean the magnetic tip. Light fine metallic dust is normal; chunks or significant buildup warrants investigation. 7. Reinstall the drain plug — new crush washer recommended. Torque to 18 ft-lbs (25 Nm).

Fill (Dipstick Tube Method): 8. Locate the dipstick tube in the engine bay. 9. Use a long-neck funnel or transmission fluid pump to add fluid. 10. Add 4 quarts of ATF+4 initially. 11. Start the engine — with foot on brake, shift through all gear positions (P-R-N-D-3-2-1) slowly, pausing 5 seconds in each. This distributes fluid through the valve body and torque converter. 12. Check the dipstick while the engine is running and transmission is at operating temperature. 13. Add fluid in 1/4-quart increments until the level reads in the HOT FULL range. Total filled is typically 4–5 quarts.

Fill (Fill Plug Method — No Dipstick): 8b. Remove the fill plug on the driver's side of the transmission case. 9b. Pump in ATF+4 until fluid begins to trickle out of the fill hole — this is the proper level indicator. 10b. The fluid must be at operating temperature when you check via this method. 11b. Reinstall the fill plug — torque to 14 ft-lbs (19 Nm).

Verifying the Fill

After refilling, drive normally for 5–10 minutes. Confirm no leaks at the drain plug and verify smooth shifting through all gears.

Common Mistakes

• Using non-ATF+4 fluid — the 8HP70 is specifically calibrated for ATF+4. Substitutions cause real damage.
• Not torquing the drain plug — 18 ft-lbs. The aluminum case strips easily if over-tightened; it leaks if under-tightened.
• Checking level cold instead of hot — the fill plug method only gives a correct reading at operating temperature.
• Not running through all gear positions after refilling — skipping this leaves the torque converter incompletely filled.

Cost Comparison: DIY vs. Dealer

	DIY	Dealer/Shop
6 qts Mopar ATF+4	$35–$50	Included
Labor	$0	$120–$180
Total	$35–$50	$150–$250

For more Dodge Durango and ZF 8HP70 maintenance guides, browse the OwnerDrop blog.

Get the full guide + every torque spec in the OwnerDrop library — OwnerDrop /pricing.