How-To: Jeep JL Wrangler & JT Gladiator 8-Speed Transmission Fluid & Filter Change (2018–2026)

⚠️ Important, Read the below FIRST in this 8 speed automatic how-to: • Park on level surface • Pressure Wash the transmission pan flange area to where dirt doesn’t contaminate threads on disassembly. • Pan's bolt torquing sequence. See the left image. https://aftermarket.zf.com/media/mast... • Following these steps ensures safe, accurate fluid filling without having to drive the vehicle on a lift or engage the driveline precariously while in the air. Why is this in the service manual? The service department has access to lifts and they aren’t going to drive every customers vehicle to get the last bit of air out of the torque converter and valve body circuits so they do this for speed, convenience, and most importantly, lessening liability exposure (like getting in an accident) aside from a final test drive. ----------------------------------------------------- If this video helped, subscribing is the easiest way to support the channel — it’s free.    / @odysseyusa   Optional support: Buy Me a Coffee or join the channel as a Member. It helps offset parts and shop costs. buymeacoffee.com/odysseyusa ---------------------------------------------------- Why watch? 1. Save hundreds doing this maintenance yourself. 2. To the point, Step-by-step visual guidance with torque specs & practical tips. 3. Confidence in performing the fluid & filter service correctly on your ZF 8HP (850RE) Wrangler or Gladiator automatic Transmission. 4. Perform a complete ZF8 Speed (850RE) automatic transmission fluid & filter service on your JL Wrangler with this step-by-step DIY guide! Whether you’re a beginner or advanced DIYer, this video walks you through the full process from pan removal to torque sequence (in the description here above), fluid filling, & ensuring your transmission is completely air-free & properly topped off. Transmission fluid options: ZF Lifeguard 8 or Mopar 8 & 9 speed. This ensures safe operation of your automatic transmission. Procedure is repeatable — I’ve done this 3 times with consistent results. Step-by-Step Refill Summary on a level parking surface: Cold fill & cycle through all gears multiple times to purge air from valve body & torque converter. Hold each gear ~15 seconds (longer than service manuals minimum). Check fluid levels while idling, top off as needed. Take a short drive to fully circulate fluid & remove remaining air. Allow the vehicle to cool & recheck within the 86°–122° F range. (See below) Final check confirms proper fill — typically only ~½ quart additional is needed. The lower the trans temp while idling, the more you’ll need to add. The higher the fill temp is, the less fluid you'll be able to get into the case, as would be indicated by reaching the bottom of the fill hole sooner with hot fluid than cooler fluid. I chose to follow the ZF instructions but use the low end of the temp range to have more fluid mass, manage fluid temp fluctuations better (slower), & with the extra mass, disperse fluid temp through the case better. • Using Lifeguard 8 or Mopar 8&9 speed transmission with an expansion rate of 1.4% & a 9-9.5qt capacity we’re talking no more than 4.5 fl oz’s difference here between adding at 86F and 122F. Parts List (links included): Transmission Fluid: https://www.amazon.com/dp/B07V46QTWM?... Transmission Filter(always lookup by VIN): https://parts.allmoparparts.com/oem-p... Transmission Pan Gasket: https://parts.allmoparparts.com/oem-p... If you need to replace the pan (damage?), you can get this whole Mopar kit that comes with the pan, filter, nuts, magnets, & gasket. Part # 68362041AC 0:00 Parked on Level Surface 0:33 Remove Skid Plate 1:00 Remove Fill Plug 1:26 Drain Pan Used 1:54 Stop the Drip from plug 2:02 Removing the Pan 3:24 Inspection 4:09 Remove the Filter 4:19 Remove the Gasket 5:06 Cleaning 5:21 Old vs Revised Gasket 6:09 Installing the New Filter 7:12 Reinstall Magnets 7:22 Lube Filter O-Ring 7:39 Clean Pan Bolts 7:49 Reinstall the Pan 11:11 Torque Sequence(Pic in Description) 11:44 Initial Transmission Fill 12:48 Warming Up Fluid/Going Through Gears 14:07 2nd Fluid Top Off 14:44 Plug/ Short Drive/ Final Top Off 14:56 Cleanup/Reinstall Skid 15:17 See Old Fluid & Tools Needed 19:19 Part Numbers Needed #jeep #jeeplife #jeepwrangler #jeepgladiator #wrangler #transmission #automatictransmission #howto #ZF8speedautomatic #maintenance #carmaintenance