Jeep JK Wrangler 42RLE
Automatic Transmission Service

Changing out your Jeep JK Wrangler’s 42RLE Automatic Transmission fluid and filter is something you should do as a good part of regular maintenance. And, while doing this isn’t something as easy as a normal engine oil change where you basically pull a drain plug, swap out an external filter and refill with oil when done, it certainly isn’t a difficult job and doing it yourself can save you a lot of money. Of course, having the right tools will make all the difference and as is the case with all my write-ups, I have included a complete list of everything you will need to make this job go without a hitch.

What you will need

• 42RLE Sump Filter & O-Ring
Part# 1-68059549AA
• (5) Quarts ATF+4
• 10,18mm Sockets
• Torx T-25 Bit
• 1/4″ Drive Ratchet
• 3/8″ Drive Ratchet
• Inch Pound Torque Wrench
• 1/4″ Drive Universal Joint
• 1/4″ Drive 3″ Extension
• Dead Blow Hammer
• Brake Cleaner
• High Temp RTV
• Mopar Lock & Seal
or Blue Lock Tite
• Flat Razor Blades
• Rags
• Small Funnel 




1. Park your Jeep JK Wrangler on level ground and remove the 3 bolts securing your automatic transmission skid plate to your Jeep JK Wrangler’s frame rails and cross member. You will need an 18mm socket for this job.
2. Place an oil catch pan under your transmission. Then, using a 10mm socket and 3″ ratchet extension to make things easier, remove all but the 2 driver side transmission sump pan bolts.
3. The 4 bolts located on the back of the sump pan can be difficult to remove due to the exhaust cross over being in the way. A small 1/4″ drive ratchet with a universal joint like the one shown in this pic will help out a lot.
4. As you can see in the photo, there is just enough space between the exhaust cross over and the sump pan to reach the 4 rear bolts using a univeral joint.
5. More than likely, you will find that the ATF+4 inside your transmission will start to leaking out of the bolt holes along the sides of your sump pan. Allow the fluid to drain as much as possible before proceeding. 6. Make no mistake, there is still plenty of ATF+4 inside your transmission so, with one hand placed under the sump pan for support, lightly tap the side with a deadblow hammer until the pan breaks free of the RTV. 7. Remove the last 2 bolts and then carefully pour out the remaining ATF+4 inside the transmission sump pan. Then, set the sump pan aside.
8. Using a Torx T-25 Bit, remove the 2 bolts securing the filter from the bottom of your Transmission. 9. Carefully pull the filter off your transmission making sure that the redish/orange O-Ring comes off the pickup port as well. 10. Remove the round magnet located on the inside bottom of your transmission sump pan. Use a clean cloth to wipe off the fine metal fuzz attached to it.
11. Using a flat razorblade, remove the old RTV attached to the edges of your transmission sump pan. 12. Using some brake cleaner, clean out the entire inside and mating surface of your transmission sump pan. 13. Place the cleaned magnet back on the dimpled seat located on the bottom of your transmission sump pan.
14. Open up your new transmission filter package and place the provided replacement O-Ring onto the pick-up tube as shown. 15. Carefully install your new transmission filter onto the bottom of your Jeep JK Wrangler’s transmission. 16. Using the factory bolts, secure the new filter onto the bottom of your transmission. A Torx T-25 Bit will be needed for this job.
17. Apply a thin bead (about 1/8″ – 1/4″) of High Temperature RTV to the inside mating surface of your Jeep JK Wrangler’s transmission sump pan as shown. 18. As is stated in the factory service manual, you will need to apply some Mopar Lock & Seal to bolt #5 in the diagram above prior to reinstalling it. I’m not 100% sure what this is but by the look of things, it’s just a mild grade thread locker so I just used blue loc-tite for this step. 19. Carefully place the sump pan onto the bottom of your Jeep JK Wrangler’s transmission and secure them in place using the fatory hardware. A 10mm socket, 3″ ratchet extension and universal joint will be needed for this job. Tighten all bolts to 14.5 ft. lbs. of torque.
20. Open up your Jeep JK Wrangler’s hood and pull out the automatic transmission dip stick which is located next to the firewall. Then, insert a small funnel into the dipstick and proceed to fill up the transmission with 4 quarts of ATF+4.
21. Reinsert your dipstick, start up your engine and allow it to idle for at least 1 minute. Then, with the emergency hand brake engaged and your foot on the brake pedal, shift your transmission lever into each position going from Park down to 1st gear and then back again making sure to leave the shifter in each position for about 30 seconds.
22. Pull out your transmission dipstick and check it’s fluid level which should be about 1/8″ below the lowest mark on the dip stick. If necessary, add more fluid as needed and recheck the fluid level after your transmission has reached normal operating temperature, approximately 180°F.

That’s it, you’re done. As is the case with any fluid change, please be sure to take your old fluid into your local auto parts store so that it can be recycled. And, if you have any questions, please let me know.Special thanks needs to be give to my friend Eric (gryph0n) for allowing me to use his JK for this write-up.



  1. Great write-up Eddie, plan on doing this before winter gets here. I have heard of people welding in a bung on the pan to drain the fluid for the next filter change,I don’t know how or if this would effect your warranty, but it sure would make a messy job a little easier.

  2. These write-ups have been EXTREMELY helpful; keep up the excellent work! This allows me to do some reading, see good pictures, then save myself hundreds of dollars by doing the job myself. I think the last routine maintenance write-up I need is changing the transfer case fluids, etc.

  3. Again, another fantastic writeup. And your timing couldn’t be better: I’m at 26,000 miles on my JK and I might do this a little earlier than 30K to have it done before the weather gets cold. Thanks Eddie!

  4. Great article. I wish you I found this in 2008 when I was flushing my tranny. This would save a lot work and also money. I tried so many times to get that pan out. I could not. I tried to remove the passenger side exhaust pipe. I could not; I even damaged the nut. I did flush the tranny and fill in with 100% synthetic fluid , but by using another method.

    Anyway, you did a great job, but halfway. The transmission holds approximately 9 qts of oil. When you replace only 4 qts, the remaining 5 contaminate the new oil you just fill the transmission. But still great article. I wish you wrote it earlier. You would have saved me a lot of frustration and money too. If you interested in knowing how I flushed my tranny without dropping the pan, shoot me an email.

    Once again great article.

    PS. You absolutely wright about fixing your own jeep. I don’t trust the technicians a the dealers. Besides, when you fix your jeep, you become to know your best friend, I mean the jeep.

  5. I know this is a “service” article but could anyone comment on the off road performance difference between the manual and automatic? I am ordering a JK and cannot decide. The auto would be more convenient around town but I don’t want to sacrifice off road capability if the manual has an advantage there. Thanks.

  6. The auto is more convenient and a superior performer off-road. Not to mention, despite some question of the auto’s high operating temps, there is clearly few complaints with the operation of the auto. The manual is frequently threaded on forums about clutch issues and various quirks with the throw-out bearings.
    I say auto.

  7. Thanks for the excellent guide! Although I have only 4000 kilometers on my JK Rubicon Unlim, (DIESEL 2.8CRD) but retained by it in the future.
    Health Vojta, Europe.

  8. Hi, some months ago I saw the motor oil change w/o mees with some oil pan valve….please let me know the name of those valve.

    Thanks….Regards from Mexico

  9. Excellent write up! It was the messiest job I’ve ever done on my JK so far. It would be awesome to have some sort of drain valve on that pan… I got ATF EVERYWHERE! Just to note one small thing I had to do different: on one of the bolts I could not use the 1/4 10mm ratchet w/ the universal joint. Instead I had to use a 10mm wrench and that was just enough to get in there and get that one free. Bolt location was the one on the driver side farthest from the front of vehicle. Thanks again!

  10. Great article, did it today. The bolts using the 1/4 10MM ratchet w/ universal joint was tough! Hard to get the bolt lose, when you finally get the universal from swiveling all around, but WHY place the muffler there? Why no drain plug for this pan? It was a lot of fluid and a messy job. My filter came with a gasket, but I didn’t use it, instead I went with red gasket sealer. 35,000.
    FYI – I did both DIFF’s with royal purple (18.00) each, did my automatic transmission pan, and also did the transfer case over the weekend. Transmission took a few hours (yes I went slow), but in all this cost me about 200.00 for all fluids and filter for everything. SAVED a bundle by not going to the dealership.

  11. Great write up, you have given me a greater insight into a transmission job that I am about to do. I need to remove the transmission cooling lines. Is there a way to do that without having to remove the radiator?
    Desperately need to know the best way to remove the transmission cooling line. I have a 2007, 4 door, jeep jk wrangler

  12. Little help here. When filling up the fluid after this service I did everything exactly as stated as far as 4 qts, shifting in neutral, checking dipstick. I am confused in what the dipstick says. Fluid s/b between lower holes when cold, between upper holes when hot. Mine is in the middle area, this is a big area. Do I keep filling until it is between the upper holes. Thanks.

  13. In step # 18 you make reference to “bolt #5 in the diagram.” The picture on my screen is far too small to indentify which bolt is #5. Can you provide a larger, clearer picture of the diagram in step # 18 Thank You.

  14. Really great write up. However, I am at my wits end trying to get to two of the four bolts at the rear of the pan (next to the exhaust pipe). The two in the middle I can reach, the ones on the end, no luck. There must be a mopar tool that they use to get to those bolts. I am going to sears tomorrow looking for a shorter 10 mm socket. Regardless, I am glad I found your write up, it was very helpful. Thanks much!

  15. Well I gave up. Could not get all the rear bolts out. I broke my 1/4 inch universal and cut my hand. Going to the dealer tomorrow. I considered removing the brace holding up the transfer case and transmission to get to the rear bolts, but wimped out. Still it was a great write up. Thanks

  16. Update: Local dealer said leak was from electrical connector to trans, and pan gasket. Required trans service to fix pan gasket. $268.00 and a month later it is still leaking. I took off skid plate and checked the leak. One pan bold in back corner by exhaust was only half way screwed in. I snugged it up and guess what. Still leaking. The dealer has lost my confidence and business. Good news, there are two Jeep dealers within 60 miles. BTW, there must be a way to push the exhaust out of the way so you can get to the two rear center bolts on the pan. Help on this issue would be appreciated. Thanks

  17. More Followup: After reading an article in 4×4 Garage (Fall 2011) about replacing the cross member I decided to remove the cross member in order to get to the transmission bolts behind the exhaust. This made it easy to drop the pan and replace filter and gasket. I used the autozone filter and rubber gasket (RTV sucks). I am convinced that the dealer did not drop the pan, replace the filter or fluid. Now I understand what the guys mean when they say stealership. If you want it done right, do it yourself……

  18. Trying this tonight with a friend but I’m curious. In the tools list it says an inch/pound wrench, but I don’t see it being used anywhere in the write up. Am I missing something?

  19. Great write up. But I needed three things to get this done: (1) a 10mm ratcheting monkey wrench to get the back screws off and on,(2) a wobble socket extension, and (3) a hacksawed-shorter 10mm socket. Took me three or four tries . . . but I did it! It is possible! Thanks for putting this page and the site together.It’s a big help, and part of what makes owning a Jeep fun!

  20. If you pull the aft cross-member / skidplate and pull the three nuts off of the bottom of the transmission mount, you can [gently] jack up the transfer case and buy you a little more room to get at those darn aft tranny-pan bolts.

    GODSPEED and Good hunting.

  21. I followed these steps. Now my tranny slips on hills and on flat surface wont shift into different gear. My RPMs stay high and match my speedometer. Oil isnt showing temp spike. HELP!!!!!

  22. I replaced my pan, filter and fluid for my trany and it is the same as Rick’s(above). Transmission won’t shift properly, especially from reverse to Drive and also won’t shift at high speed 80-100kmph

  23. I had to use Joe’s tip. I could not get the back center bolt in the transmission pan without lifting the transmission a couple of inches.

    Also, I would throw away the gasket that you get with the filter. I put it in and started filling. After the first quart, the next two just leaked right out. Big mess. Big pain in the butt.

  24. Changed Fluid filter and went with the PML Aftermarket Pan I didn’t have any issues using these instructions. The three bolts in the back are challenging but it is possible to get them out it just takes patience and persistence to do so. The PML pan comes with allen head bolts which I think are a bit easier when a ball tipped allen tool is used. Thanks for the great write up.

  25. I use a pump and evacuate the ATF fluid through the fill tube, then undo the screws holding the pan on. Since this is a regular maintenance item (60,000 ~+/-) you can also install a plug to drain the fluid. After you drain the fluid, you can easily install an auxiliary cooler and in-line filter at the front of the Jeep. The added cooler is really needed on the ’07-’11 JK Wranglers since Jeep went cheap on the AT cooling.

  26. I got a bit of a dif prob with my buddy’s 2010 wrangler he was changing slave cylinder and dropped not on but two of the plastic ends into the tranny now can’t geg them out so going to have to pull tranny with basic tools and remove them i have the skills to help him out but never did this year and make befor will it require any specialized tools befor i get started or would u recommend just pulling tranny and sending tranny shop thank you any infinite would be approshiated

  27. Mine took over 5 quarts of Carquest brand ATF+4 & I think it’s leaking but the fluid reads 1/3 of the way over the cold mark after doing the shifter dance dipstick procedure. How did everyone else’s come out?

  28. Trans filter came with a gasket, used that instead of RTV. The 4 bolts under the exhaust were really a bear.

    Also, be prepared for a second shower of ATF when the filter comes off. Caught me by surprise.

  29. Yes, the exhaust cross over is a serious pain but I got the bolts out. It’s getting them back in that’s the real challenge! Also, in your list of “What you will need” You state (5) Quarts ATF+4 then in the instructions you say to fill it with 4. That was a little confusing. 4 quarts hit the mark just right so I’m guessing the 5th quart is just to top it off if needed.
    Thanks for the write up, Big help!

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