Need an advice on my 2004 42RLE mini overhaul

It is true the valve body seems to be dirty with grime or something. Maybe micro shaved metal dust, don’t know what is it.
Now the plan is to assemble the new valve body from ebay (seems to be cleaned and reassembled) and the new solenoid pack from Mopar using the seals from the transgo shift kit. Not that I think that the problem was with the accumulator, apparently they look OK, but if I am doing it, then yeah, new seals.
 
Out of all the reasons that the maintenance guide lists, Seems like it is now narrowed to
Valve body - #1 ball check or LR switch valve sticking - may also set code P0731(51)
Or leaking LR clutch seal, as everything else is eliminated.
Will start assembling everything back and let’s see what I get.
 
Ok, so assembled everything and it seems to work fine at least based on an hour of driving.
I have installed the temperature gauge so I see the pan temperature. Maximum that I am able to get is 148F. I need to get to the area of 180F, as with my Derale active cooler it is the worst case scenario.
 
I would like to list here the steps that I have performed as a part of the mini overhaul.

So the motivation of the mini overhaul was having shifting issues, not going into reverse when hot, or slipping in first when hot.

From reading through the manual and 42RLE guide in the resources section, I came to conclusion that majority of potential problems in 42RLE are caused by valves, pressure switches, solenoid electronics and accumulator pistons. The most problematic piston is LR (low reverse), as it seems like it is the accumulator that is supposed to deal with highest pressure in reverse and it has oil coming to it from the side. I investigated how the LR piston can be improved and found the Sonnax piston fix.

So the steps I have performed:

1. Jack the Jeep and get it on 4 stands,. But like relatively high, as you need space. Remove the transmission skid plate and Drop the transmission pan and remove the filter to start draining it. Ideally to open it overnight, so that everything comes out by the time you have to crawl under it.
The transmission pan bolts are 10mm and the filter has 2 screws that are T25 torx.

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2. After you are done draining ( I got out something like 6 quarts at least, maybe because I have Derale cooler and it adds volume), you need to disconnect front driveshaft from the front diff, so you get some space to access the transmission shift linkage. No need to remove the front driveshaft, only to lower it.

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3. Now, the are 3 things that needs to be disconnected from top of the transmission: Solenoid pack connector, shift linkage and transmission range connector. Solenoid pack connector is the real pain in the ass, as access to it is blocked by the exhaust.

4. Disconnecting the shift linkage. The shift linkage is help by 1/2 inch head screw. You need to loosen this screw, don’t open completely. I used 1/2 socket and small Ratchet. For this purpose it does not matter in which gear the transmission is, but I think that it is easiest to access the screw head when transmission is in park. However, I think that others will find it easier in 1.
After you loosen the screw you need to slightly tap up the shift linkage metal. You might want to spray some WD40 or something if you have rust. I didn’t, so it came off with some slight taps.
Before you remove the connector, Learn which position is 1 and which one is Park. The reason for this is that now you need to more the lever into a hidden position that cannot be done by the gear selector. This hidden position is right after 1, like you one beyond one. It is the last possible position, so you know that you there because the lever will turn anymore.
I used big plier or 3/4 to drift the lever itself.

Also, use some sand paper and polish the lever. The reason for this is that if you don’t do it, all the rust and dirt will prevent from valve body to come down.

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5. The next thing is the TRS connector right next to the shift lever.
All you need to do is move the red tab to the left side and pull the connector while pressing on the green tab. It comes out really easy.

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7. The next step is to remove the solenoid pack connector, the 3rd and the most pain in the ass.
So this connector is very tricky to access and you need to perfectly know what are you doing, no any force to be used. If you rip any wire in it, or damage it in any way this will become a nightmare.
I was not able to take a picture of this connector when it was assembled, as it is completely blocked by exhaust and the tub itself, but took a picture of it from underneath after dropping everything.
You can see it also has a red tab and brown press connector.
So, what you need is to access the connector through whatever gap you have between the exhaust, tub and the transmission itself, move the red tab with you finger or screwdriver and press the brown tab and pull it up. After the red tab is moved, it comes off really easy.

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8. Now you have all 3 connections from top disconnected and the shift lever is in the after 1 position.
If you are not sure in which position the shift lever is, do not go further, future this one out. The valve body will not come out unless the shift lever is in the hidden position.

9. Now you remove all 10mm hex bolts on the valve body, nothing else. The moment that you finished the last bolt, valve body seems falls out. Have some rope or something holding it or just hold with your hand when dealing with last bolt. You don’t want this to fall on your head.

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10. 2 accumulators that are located vertically inside the transmission will jump out together with the valve body. Valve body was the only thing holding them inside. Make sure you catch these or find them on the floor - this is what happened to me.
The 2 holes are round holes in the pic.

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13. Now you decide what to do.
What I did is to buy new solenoid pack from Mopar.
You can see the old vs new in the pics. The pack has a date code (year) on it, make sure that you see that it is actually new.
I think that the solenoid pack is the one of the main causes of limp mode issues, and putting a new one is just a peace of mind thing.

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14. The next step is the pistons.
The 2 pistons that fell out - I just took the seals (transgo kit has a double seal) from the transgo shift kit and put them on the closed side of the pistons. Open side I kept the original seal.
Installing them back was pain in the ass, as they want to fall out. Be careful not to damage seals when installing them back.
I took a piece plastic and drilled a hole in it, so I can attach it to the transmission with pan bolt so this will hold the pistons in while I am putting the valve body back.

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15. LR piston.
My LR piston was too scratched and I came to conclusion that I need a special Sonnax piston.
This piston comes as a kit, and you install instead of the original piston.
This is how it looks like.

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16. Install the sleeve into LR accumulator
Make sure that the sleeve is all the way up. Has to be like this, other wise you will block the side oil passage.
Then install the new piston with the springs that it comes with.
I also bought new snap ring and the green accumulator cover and installed them.
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17. I bought remanufactured valve body from eBay. My assumption was that all it takes is somebody taking a valve body, opening it, cleaning inspecting and replacing anything worn out and assembling back. This reman valve body came with TRS installed.
I didn’t go and buy new TRS, because unlike solenoid pack it is nothing complicated. It has a thermistor for temperature and 4 pins that detect the shift lever position.
On this valve body I installed the new solenoid pack with its new pack filter.
The shift lever was already on the correct position (next after 1), which basically catches the parking lever to the valve body.
Had to push back the new valve body, it didn’t go easy, had to tap with rubber mallet to get it in.
 
18. When the valve body was already hanging by its screws, I just removed the piece of plastic that was holding the the accumulators.
Fastened all the screws by the spec, installed the filter and installed the pan.
 
Next step was to connect the solenoid pack connector. Push down and move the red tab to lock..
After that I again lowered the front driveshaft, for easy access to TRs and shift lever.
Then connect the TRS connector( push down and move the rad tab to lock).
Then the shift lever.
Sanded it slightly with sandpiper ( I wish I would do that before installing it, when it was out) I moved the lever in the middle position using pliers and then installed the linkage.
After linkage installed, the linkage needs to be tested with engine off (I still didn’t connect the battery back at this point) and wheels in the air. No parking brake applied.
Move the handle in the cabin into park. Try to turn the rear driveshaft( transfer case in 2H , it should click inside the transmission and hit the parking thingy).
If passed,
Move to neutral. Driveshaft should spin fine and free.
Then move through all positions, make sure you hear the click on every shift. After you are back to park, test the driveshaft again.
If all passed, your linkage is fine, and mechanical assembly is OK.

Connect the driveshaft back to the front diff.