42RLE Shift Failure

[05ELJay]

05 LJ 42RLE 155k. Alrighty, this has been a total crapshoot for me. Took the Jeep in to have the transmission rebuilt, was on its way out. Had been going into limp mode off and on. Would drive fine for a 100 miles and then It would decide it doesn’t want to anymore. Fast forward what was supposed to be about a week rebuild has now become 6 weeks with no Jeep and a whole lot of questions gone unanswered. I feel like the shop has definitely been giving me a run around on some things. The shop says that it will shift fine up on the lift, pressure tests are good BUT once they drop it down to drive it around it won’t shift at all and/or shift very rough, apparent loss of pressure/prime. They are equally as fed up with the issue and are willing to go as far as putting in a remanufactured transmission to see if it solves the issue. They have had the transmission apart upwards of 4 times and can’t find any obvious issues. I don’t know if there is a correlation between the tire size (35’s) and this issue, was never a problem before rebuild. Had them install a new PCM from WranglerFix, fix some chafed wires, yet they’re still beating around the bush. It drove before and now it won’t that’s all I can say haha.

 

[TJ Hunnicutt]

Wow, that's a strange one. The differences, that I can think of, between being on a lift and on the ground that could make a difference are:
1) No drag on the wheels. The tranny can easily turn the wheels because it only has to overcome the mass of the wheels/tires. There is very little torque being applied through the tranny 'cause it's just freewheeling. When on the ground, it has to move the Jeep.
I'm betting there is still something amiss in the tranny that, when power/torque is actually being applied through it, it can't shift correctly (something binding up maybe?).
2) Un-compressed suspension while on the lift so, possible suspension components coming in contact with a wire or something when it's on the ground...seems pretty unlikely but it's a thought.

 

[TJ Hunnicutt]

Are they willing to put in the rebuilt tranny for the same price that they quoted for them rebuilding yours? If so, I'd say go for it.

 

[Jerry Bransford]

Contact Mark at www.wranglerfix.com who can figure out if your problems are caused by the PCM. Likely they are. 2005-6 have programming bugs in the PCM that affect the 42RLE transmission. The buggy TCM inside the PCM can make software bugs look like transmission problems.

 

[AjRagno]

I've checked with shops regarding rebuild and replacement options a few times. One shop I spoke with in early 2018 quoted $1800-$2800. When I checked with them again a couple months ago the quote had gone up to $3800-$5000. When I asked about the dramatic increase they explained they'd since had a customer with a 42RLE who kept coming back with problems until they had to eat the cost of having a dealer rebuild it. They now use Mopar sourced parts and sell the service as a dealer rebuild at 1/2 the labor.

Considering that it's already at a shop I'm not going to speculate on the issue. If they did the rebuild, it's on them to figure it out.

 

[Jerry Bransford]

I've checked with shops regarding rebuild and replacement options a few times. One shop I spoke with in early 2018 quoted $1800-$2800. When I checked with them again a couple months ago the quote had gone up to $3800-$5000. When I asked about the dramatic increase they explained they'd since had a customer with a 42RLE who kept coming back with problems until they had to eat the cost of having a dealer rebuild it. They now use Mopar sourced parts and sell the service as a dealer rebuild at 1/2 the labor.

Considering that it's already at a shop I'm not going to speculate on the issue. If they did the rebuild, it's on them to figure it out.

Read the info in post #4 above.

 

[05ELJay]

Contact Mark at www.wranglerfix.com who can figure out if your problems are caused by the PCM. Likely they are. 2005-6 have programming bugs in the PCM that affect the 42RLE transmission. The buggy TCM inside the PCM can make software bugs look like transmission problems.

Thanks Jerry, I have been in contact with Mark and had ordered one a couple weeks back. Said that the codes it was throwing are indicative of PCM failure. By the sound of it the shop installed the WranglerFix but the issue still persists in some form. They had it sent to the dealership to get the original PCM re-flashed, however to no avail, tech said it was internal to the transmission and not PCM related. Shop had it towed back to them, they found bad wiring in between block and firewall, said it “fried something” in the valve body so had a new valve body installed. Just one thing after the other..