2006 LJ 42RLE to AX-15 Swap

[tangomikefoxtrot]

The swap was finished on my LJ recently, sorry on video and post quality I have a Kentucky public education....

To start off: I am so happy with this swap, AX15 feels amazing. (i have 35's, 4.88 gearing, it drives great)

42RLE died October 2023 overheating while crawling in the armpit of South Texas, being broke and busy military I garaged the Jeep and casually dug around on forums for a few years gathering a parts list. At first I saw some posts where a user retained the Auto PCM with the shift solenoid and sprocket from inside the transmission attached to the neutral safety switch. In my opinion, that method is very sloppy and dangerous as its leaving the ability for your vehicle to be able to start based off you pinning some metal together with zip ties and letting the harness dangle.... I also noticed most times where a user would ask for help with doing the swap a few of the common users would simply shill that an auto is better, to "sell the jeep" or to give up as it was too hard. Finally I saw @freedom_in_4low 's for his manual to manual swap and one of @mrblaine 's responses and my thinking changed. Thanks a lot to you two by the way.

For the sake of documenting my steps in case anyone else wants to recreate this swap I'll type out my steps here.

Why did I choose the AX15? Very simply because I found one for $200 and I loved the last vehicle I had with one in it.
@mrblaine at some point stated the way to approach this is to simply build the jeep as if it came from the factory as a manual. That is the easiest way to approach this.
I broke out the part diagrams from the pinned tech manuals and build a list of parts to acquire.

For the CPS issue I did choose to buy the Advance Adapters bell housing, for PCM I chose to just buy a new one from @Wranglerfix instead of guessing about condition and SKIM from ebay PCM's. Thank you Mark.

points to consider as i saw people arguing online.

• you do not need new driveshafts, the ax15 and the 42rle might be an 1/4 inch off in length but the tcase mates and the transmission mounted just fine onto a skid plate
• you do not need an entirely new center console
• If jeep is a 2005 or 2006 i know for a fact there is a pressed sleeve into the rear output of engine that needs to be cut out to insert the pilot bushing from your clutch kit
• you WILL need a new PCM or send your existing PCM to Mark @Wranglerfix if they are able to remove the auto nonsense from the PCM.
• input shaft on the unknown 90s ax15 was the exact length as the shaft on 42RLE

Remove from Auto jeep:

• brake pedal assembly
• the master cylinder plate on firewall
• the harness running from computer to transfer case
• the 42rle and associated linkages
• the cooling lines from 42rle
• shift plate
• shifter
• Park/Neutral cable that runs from shifter to ignition cylinder (jeep will ding as if there is a key in the ignition, or you remove DOOR DEFEAT fuse to kill the ding)
• starter (you need a new manual starter)
• flex plate

Variables that might matter

• i have a UCF belly up skid that has multiple mounting locations on it. I have no idea if the OEM shovel skid plate can be maintained
• my jeep is a 2006 with a 1.5inch body lift
• once harness is off this is a good time to do stuff like O2 sensors and injectors

Install onto Jeep for manual

• PCM
• Harness
• Flywheel of your year jeep
• Clutch + pressure plate that matches year of transmission
• Bellhousing onto transmission (OEM CPS location is very important)
• ax15 transmission mount onto transmission
• pedal assembly
• new starter
• transmission mated to engine
• skidplate to jeep

Problems you might run into

• Doesn't start after swapping everything... check your grounds you just replaced an entire harness
• before install of new harness check for any exposed wire, and there is never a better time to reloom than holding that new harness
• reverse light : its two wire to two wire, just cut the connectors off and splice in a Male and Female two prong combo from parts store

Parts List

• 712590L | BELLHOUSING 2005 & 06 Advance Adapters
• AX15
• 52128017 | Pedal assembly
• CC649061 | Clutch Master + Slave Cylinder
• LFW484 | LUK NSG370 Flywheel
• 05-065 | Luk: AX15 Clutch + Pressure Plate
• 56041012AE | 2006 TJ MT Starter
• PCM WranglerFix.com (Manual PCM for 2006 + my auto VIN)
• 52128017 | Wiring-Engine harness (goes to Tcase)
• 52058546 | TJ Manual Transmission mount
• UNK | Jeep TJ Wrangler 4.0L to Manual Transmission Inspection Cover
• 52059661AC MOPAR Floor pan cover
• Clutch safety switch
• New hardware

Thank you for reading. I'm sure I might have forgot to type some information in the post, and even forgot when filming the video. If you have any questions maybe I can help. The hardest thing on this is probably cutting out this sleeve to make room for the pilot...and chasing grounds.

 

[Chris]

Having owned TJs with both manual transmissions and the 42RLE, I will not dispute that for rock crawling and technical off-roading the automatic is superior.

However, in every other situation (namely daily driving) the manual transmissions make the TJ so much more enjoyable to drive.

 

[D's Jeep Wrld]

Going from a 42rle to a Ax15 in my 05 Lj was one of my best decisions (street/dailying wise) I can finally do what I like to do in my Lj Alot easier to initiate drifts/burnouts etc. ,It may suck for crawling but I may do a 4spd atlas or doubler at some point in my build

My 42rle was going out and I didn't see myself spending 4k for a decent unit that'll handle my shenanigans lol,So an Ax15 was my solution !

 

[lBasket]

Alot easier to initiate drifts/burnouts etc.

Average TJ owners concern right there

 

[D's Jeep Wrld]

Average Lj owners concern right there

FIFY

 

[tangomikefoxtrot]

Having owned TJs with both manual transmissions and the 42RLE, I will not dispute that for rock crawling and technical off-roading the automatic is superior.

However, in every other situation (namely daily driving) the manual transmissions make the TJ so much more enjoyable to drive.

Going from a 42rle to a Ax15 in my 05 Lj was one of my best decisions (street/dailying wise) I can finally do what I like to do in my Lj Alot easier to initiate drifts/burnouts etc. ,It may suck for crawling but I may do a 4spd atlas or doubler at some point in my build

My 42rle was going out and I didn't see myself spending 4k for a decent unit that'll handle my shenanigans lol,So an Ax15 was my solution !

Just returned from a Texas rock crawl trip. I gotta say, wheeling this with the AX15 was /almost/ no different than my 42RLE when I'm in 4-low. Obviously some clutch control here or there, and even more-so when in 2or4-hi. But, my jeep is already geared to compensate for the TERRIBLE overdrive gear on the 42RLE. So yea, gear it like a tractor and it'll crawl. I do not at all regret my decision.

Daily driving, hoo boy its fun. Easily spin tires dumping it in first, way easier than punching the 42RLE at the same gear ratios

 

[D's Jeep Wrld]

Just returned from a Texas rock crawl trip. I gotta say, wheeling this with the AX15 was /almost/ no different than my 42RLE when I'm in 4-low. Obviously some clutch control here or there, and even more-so when in 2or4-hi. But, my jeep is already geared to compensate for the TERRIBLE overdrive gear on the 42RLE. So yea, gear it like a tractor and it'll crawl. I do not at all regret my decision.

Daily driving, hoo boy its fun. Easily spin tires dumping it in first, way easier than punching the 42RLE at the same gear ratios

Hahaa Thats awesome Yeah 5.13's with the AX15 allowed me to do burnouts on 2nd gear if i wanted to lol.....1st gear was useless on the street but probably woulda been great on the rocks !
With the ford 9"/Trophy truck axle geared to 4.56s should be great on 35s going 80 down the highway (once im done).....im not too excited to see how it does out on the rocks

 

[tangomikefoxtrot]

Hahaa Thats awesome Yeah 5.13's with the AX15 allowed me to do burnouts on 2nd gear if i wanted to lol.....1st gear was useless on the street but probably woulda been great on the rocks !
With the ford 9"/Trophy truck axle geared to 4.56s should be great on 35s going 80 down the highway (once im done).....im not too excited to see how it does out on the rocks

I'm choochin with 4.88, 1st is actually useable on streets. Its GREAT for traffic. But I can 100% launch in 2nd. 4-Low + 1st or Reverse is actually very similar to an old tractor haha.

 

[driver 06]

Nice. Thanks for posting tangomikefoxtrot. I'm looking to swap to a manual and it seems like the need for new driveshafts are for the stock height and skid plate, does anyone know anything about that?

 

[macleanflood]

Nice. Thanks for posting tangomikefoxtrot. I'm looking to swap to a manual and it seems like the need for new driveshafts are for the stock height and skid plate, does anyone know anything about that?

Plenty of forum posts on doing AX-15 swaps. More than likely once you've completed your swap you'll need to measure yoke to yoke and order custom shafts.

-Mac