Jeep Wrangler 392 8hp 75 transmission filter change - most overlooked maintainence

[Infidel09]

I have close to 61k miles on my modified Jeep Wrangler. The motor and transmission have been tuned and I run flex fuel E85, you cant beat the prices...I have noticed that the downshifts were not as strong as they were. Time for a fluid and filter change in the transmission. In order to change the filter you have to purchase the kit that comes a new pan. The pan removal is very simple you should have 6 quarts for the refill.. Expect to use about 4.5... There is a fill hole on the side that you can remove first to empty out some fluid and then the pan. The pan has magnets on the corners - you'll see in my pics that sludge build up is not good. I can only imagine how bad the filter was. Reinstall the new pan and fill up to the drain hole. Repeat the process and refill. I ended up using 4.5 quarts...I checked the amount that was removed and it matched.
The test drive was more than enough proof. My downshifts will pin you to the seat and break the tires loose with ease. This might be the most overlooked maintainence on the Jeep. The kit and Mopar 8&9 speed transmission fluid were about $225 together on amazon.

Amazon.com: A-Premium Transmission Oil Pan Without Drain Plug Compatible with Jeep Wrangler 2018-2024, Grand Wagoneer 2022, 2.0L 3.0L 3.6L 6.4L : Automotive

Buy A-Premium Transmission Oil Pan Without Drain Plug Compatible with Jeep Wrangler 2018-2024, Grand Wagoneer 2022, 2.0L 3.0L 3.6L 6.4L: Pans & Drain Plugs - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

a.co

https://a.co/d/08BQKQuf

 

[stylerc]

Good reminder. These ZF boxes get lazy when the fluid’s cooked, especially on tuned/E85 setups. The pan/filter swap and fresh ATF+4 can make a night and day difference in shift feel and solenoid response, and that sludge on the magnets tells the story. Way cheaper to service it early than chase weird shift codes later.

 

[fspalt09]

When should you consider this? I have a 22 with 32k miles about to head out on a road trip.

 

[hardhat]

make sure you are using the right fluid. I thought atf 4 was a different spec. I used the ZF Lifeguard 8 fluid. I thought there was a mopar fluid equivalent as well but thought it was the mopar 8&9 speed fluid.......

There are so many different fluids out there and thing that claim to be universal or good enough....Just a word of caution. Even if you used the wrong fluid it would probably work OK for a while only to possibly mess things up down the road.

Amazon.com: For Audi BMW Jaguar Land Rover Set of 9 Liters Auto Trans Fluid ZF LIFEGUARD 8 : Automotive

Buy For Audi BMW Jaguar Land Rover Set of 9 Liters Auto Trans Fluid ZF LIFEGUARD 8: Transmission Fluids - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

This is what I used and believe it to be the correct fluid

 

[Viking Jeeper]

I have close to 61k miles on my modified Jeep Wrangler. The motor and transmission have been tuned and I run flex fuel E85, you cant beat the prices...I have noticed that the downshifts were not as strong as they were. Time for a fluid and filter change in the transmission. In order to change the filter you have to purchase the kit that comes a new pan. The pan removal is very simple you should have 6 quarts for the refill.. Expect to use about 4.5... There is a fill hole on the side that you can remove first to empty out some fluid and then the pan. The pan has magnets on the corners - you'll see in my pics that sludge build up is not good. I can only imagine how bad the filter was. Reinstall the new pan and fill up to the drain hole. Repeat the process and refill. I ended up using 4.5 quarts...I checked the amount that was removed and it matched.
The test drive was more than enough proof. My downshifts will pin you to the seat and break the tires loose with ease. This might be the most overlooked maintainence on the Jeep. The kit and Mopar ATF 4 transmission fluid were about $180 together on amazon.

Amazon.com: A-Premium Transmission Oil Pan Without Drain Plug Compatible with Jeep Wrangler 2018-2024, Grand Wagoneer 2022, 2.0L 3.0L 3.6L 6.4L : Automotive

Buy A-Premium Transmission Oil Pan Without Drain Plug Compatible with Jeep Wrangler 2018-2024, Grand Wagoneer 2022, 2.0L 3.0L 3.6L 6.4L: Pans & Drain Plugs - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

https://www.amazon.com/dp/B07VFJYQJ3?ref=ppx_yo2ov_dt_b_fed_asin_title

View attachment 52849

I believe this is the first time I have heard of someone doing this service on their 392. Mine is a low mileage garage queen but thanks for the tips.

 

[RadMan]

make sure you are using the right fluid. I thought atf 4 was a different spec. I used the ZF Lifeguard 8 fluid. I thought there was a mopar fluid equivalent as well but thought it was the mopar 8&9 speed fluid.......

There are so many different fluids out there and thing that claim to be universal or good enough....Just a word of caution. Even if you used the wrong fluid it would probably work OK for a while only to possibly mess things up down the road.

I believe you are correct. This is the Mopar fluid that I used.

https://www.amazon.com/dp/B07V46QTWM?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_10

 

[Infidel09]

I believe you are correct. This is the Mopar fluid that I used.

https://www.amazon.com/dp/B07V46QTW..._hzsearch_conn_dt_b_fed_asin_title_10[/QUOTE]

Hey guys big shout out to HARDHAT... I used the wrong transmission fluid...The one you need is listed above it specifically says the 8&9 speed Mopar 8hp transmissions. I tried editing the post but I still haven't figured out how to do that - but once again thanks for looking out for me. I owe you a cold beer Hardhat...