Any tips for changing the automatic transmission fluid in a TJ

TerryMason

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I've got 65,000 miles on my 2005 TJ, and my manual says that it's time to change the fluid and filter in my 4-Spd. Automatic 42RLE Transmission. I've changed the fluid in an old buick once, and remember it being an incredibly messy project, with me having to throw my shirt and pants away at the end :rolleyes:

Any tips or gotcha's on this one? I've read some places that adding a fluid plug is a good move - what do you guys think? I assume that I'd be able to drain it easily, and could probably fill it though the dip stick.
 

tip #1 wear gloves :)

take a quick spin around the block to warm the fluid up.

park on flat surface.

starting at one end of the pan loosen and remove all bolts.
When you have like 6 bolts left loosen them all, but keep them in.
if pan has not dropped yet, gently pry it. Fluid should start pouring out, kinda like your pouring a drink. then start removing bolts so pan tips further down.
The more you loosen the bolts, the more the pan will tip and the more fluid will pour out.

eventually you will have to remove the final bolt, hold on to the pan, remove bolt, dump rest of fluid out.

I don't know anything about the new auto's, but I will assume a filter is bolted in or just pressed in.
remove, more fluid should come out.

Clean pan of fluid, any shavings and gasket.

add new filter, put gasket on, add tiny bit of silicon to gasket to hold in place bolt up, tighten bolts finger tight then tighten down like you would a wheel.

Not sure how much fluid is added ( pints?) fill it through the dipstick. Better to low thwn over filling at first.

Start Jeep up, foot on brake, run it through the gears. I would do 1st gear/reverse/2nd gear reverse/ 3rd etc

put in park, check for leaks then check dipstick, add as necessary.

dispose of fluid properly ( auto parts store dispose of them for free, I think)




Its been years since I have done this ( worked at Shell for a few years) but I think I got everything....

Somebody else jump in.
 
Thanks for the tips. From the sounds of it, that first part (removing the pan) is going to be the hard / messy part.

I'm just beginning my research, and I had originally heard of drilling and tapping a hole in the transmission pan to help drain. I then found that most people remove the transmission hose from the radiator to drain it, using this method:

  1. First, drain the fluid from the pan, replace the filter, the pan gasket, and reinstalled the pan
  2. Fill the transmission to the proper level using the proper type of transmission fluid.
  3. disconnect the return transmission line (the line in which transmission fluid flows from the transmission cooler back to the transmission), located near the bottom of the radiator. There's two transmission lines connected in this location, and the bottom line is usually the return line.
  4. Once the line has been disconnected, attach a clear piece of tubing to the transmission cooler, the same diameter as the transmission line, approximately 5-6 feet long, using the transmission line clamp to secure it.
  5. Place the unattached end of the clear tube in a plastic, one gallon milk container and place it where it can be seen (like not under the car).
  6. For the next portion of the procedure, make sure that the parking brake is set prior to continuing. Start the engine. The transmission needs to be put into "Drive" so the torque converter fluid is changed as well. Some transmissions will only circulate fluid through the torque converter only in drive. This especially applies to the electronically controlled transmissions.
  7. After approximately 4 to 5 quarts of fluid have been pumped out, you should notice a change in the color of the fluid. It should go from a brownish red color, to a bright pinkish red color. When this happens, all of the old fluid has been replaced with new fluid.
  8. Be careful not to overfill the transmission during this procedure. When completed, reconnect the transmission return line to the transmission cooler.
  9. Check the fluid level as you normally would, and add fluid as required.
the more I get into this, the more I've started wanting an external transmission fliter, like this one:
Perma-Cool 10677 - Perma-Cool Deluxe Automatic Transmission Filter Kits - summitracing.com
I could change the filter every 10,000 miles or so, and supposedly really extend the life of the transmission. An added bonus would be that I'd be able to easily mount a trans temp gauge.


This whole thing came about on my last offroading trip - I smelt something burning, and assumed it was someone in front of me. I now have a sinking suspicion that it was me, but without a temp gauge, I'm only guessing.
 

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Add an external cooler and temp gauge, as well as a deep transmission pan, if you want to extend the life of your auto. The deep pan will help all those Jeep autos that starve for fluid on steep climbs.
 
Terry I am at work but when I get home I could get you the part numbers for CD's deep well Transmission pan the kit comes with everything you need, new filter extender block, screws, pan gasket, and filter. The pan comes with a drain plug plus a second location for temp sensor .

I also run a over sized transmission cooler in series (post radiator). Its made for a for pick-up but it bolts on to the two 'V' front cowl supports. Picture to follow later today. For every 5 degrees cooler you run your automatic transmission you extent the life of the oil 15,000 miles. I am running in the summer time around 145 degrees and up to 165 on the rocks.

P5007793AB Cast Aluminum RWD Deep Oil Pan Package (A-727) $229.00, P5007794AB Cast Aluminum RWD Deep Oil Pan Package (A-904) $199.00
 
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Thanks guys!

I think I may take your advice, and run a deeper pan. I'd also like to have a temp gauge as well. Utah where did you mount your temp gauge?
 

Oh yeah - If I run a bigger pan, will I have any problems in the future with fitting a skid plate?
 
As to where I mounted my temp gage: I mounted it next to the left side pillar on my aftermarket roll cage, but by tomorrow afternoon I will most likely move it lower or on the steering column. It severely limits my view outside the jeep...but it does look cool sitting there. (Like a diesel truck gages)
Bellie up pan: So far we haven't had a problem with two of the jeeps in our group that run deep transmission pans and bellie pans. (One is Fab-tec and the other is Rock Krawlers).
 
i looked everywhere, and I can't seem to find a deep pan for my transmission (I've got a 2005 with a 42RLE). Hopefully I'll find one soon.
 

this is how I mounted my Transmission cooler, I used those offset clamps and used two , one on each side to mount them to the 'VEE" bars that support the front clip.
Now have you tried the stealership Terry? For the deep pan? it was the cheapest around when I was looking.
 

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Utah-Jeepster, I would like to add an external trans cooler inline with the factory unit built into the radiator. Can you tell me more about how you did yours? Cooler brand used and parts needed to complete the job? I have a 2006 TJ daily driver with the 42RLE overdrive trans running 33x12.50 MT's we live in the desert and the heat concerns me. I just bought the Jeep with only 35K miles so the trans is still in good condition, we just did a lift and added the larger tires.

Mark
 
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GUARDIAN: Brand? I am sorry there I really didn't pay attention, I just went down to Auto Zone and bought one that looked like it would fit the "V" bars its for a 79 ford 1/2 ton pick-up.
The kit came 3/4's complete for my proposes, I also used rubberized hose clamps that I used to bolt the Cooler to the two radiator supports. (McMaster Carr # 3225T22)

The next part is a little more difficult that is crawling under and disconnecting one line off the radiator to find the power side of the fluid flow and which one is the return line.
I cut the hard line on the return side of the radiator and used a brake flaring tool to flare both sides of the hard line, (not really necessary but I am weird), and hooked on the hose and clamped it into place. Then I ran that to the top on the new cooler and took its lower (return line) back to the transmission return line. Strsapped everything in tight and I was done.

I also ran double hose clamps and flared the hard ends to make sure no errant branch could pull the lines apart. The first time I pulled a line off the radiator, it was the power side and I got soaked with transmission fluid so a nice bucket would be handy. But you want to cut the return line coming out of the transmission, close as possable from the radiator so you can run the rubber line along the radiator without littling it droop, let the radiator do the first cooling then the secondary one down stream.
 
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