TL;DR, I hate my 42RLE, I don't have the money for Novak bits (especially since I live 1 ocean and 2ish continents away) so I made my own Manual conversion using some CAD, a hole saw and a local sheet metal supplier. She's got about 1,400km on her since her surgery, going strong with a hint of quirk.
The long way, WITH PHOTOS!
I'm going to avoid talking about things that have already been discussed on the matter and just stick to what i think hasnt been talked about or at least what i havent seen talked about.
My goal was to not buy the Novak bell housing, not swap PCMs, learn some new skills, be a cheap bastard and best of all, sink some more blood sweat and tears into my TJ, i like my TJ, i dont want someone else's TJ that has a manual in it, mine runs well and has a bunch of cool stuff on it that almost no one else in this country has on theirs and i like it that way.
I live in the middle east, rock crawling isn't all that popular so i learned my driving in the desert, while i know most of you guys in the west prefer your TJs on the rocks, they've actually got some great features that make them great in the desert, and the way we navigate the dunes here on a technical standpoint has sorta evolved around the geometry of a solid axle vehicles; mind you, my assumptions are based on videos of Americans and Australians hitting up dunes, so i might be a tad ignorant on the west's techniques.
The issue: we drive around at fairly high speeds compared to rock crawling and at relatively high RPMS, actually usually we're closer to redline than idle, so between the torque converter, the clutches, poor gearing and slippage you get in the 42RLE once you hit a certain skill level it starts to become a bit of a hinderance, not to mention that even with trans oil coolers the size of an AC condenser these 42RLEs just love overheating and begging for expensive rebuilds every 2 or 3 years (assuming you go out as often and as hard as i did.....spent a year with basically no 1st gear or Reverse because i just didnt wanna cough up the moola). So here's the goal: Manual trans swap for the cost of my last 42RLE rebuild invoice.
Below is a video of me in my automatic (2022, so around the time i lost reverse), barely keeping up with my friend in a very beat up NSG370, driving around in 4low because his TJ pops out of 1st and 2nd. Also a video of a friend of mine following a local club convoy...for context.
As i've reached my daily youtube upload limit..... https://drive.google.com/file/d/1BLlZOu3fWkKbz7Eh-F8IREOZWar4zC1s/view?usp=sharing
It cost me AED6200 (tax included) to rebuild my 42RLE on it's 3rd and final rebuild) which is $1,688 circa. August 2023.
The thinking: the Novak adapter is basically just a flat face for the late model sensor to sit on with a threaded hole with extra steps because making cool products is cool....so what if i make a hole in an AX15 bell housing and then make a mount of some sort to adapt it.
So i'm lucky here, i have amazing friends, a friend who fixes TJs for a living happened to have a broken NSG laying around that i pulled the bellhousing off of and another friend with a spare AX15 that i pulled the bellhousing off of as well...we went back to friend no.2's place and we took some measurements to compare, a few 3D prints, some adjustments and about 4 hours later we know where the hole is meant to go relative to the input shaft.
Designing with my friend Mermaid
We confirmed our design against the AX15 bellhousing.
AX15s are a dime a dozen at scrap yards here so that was my smallest hurdle
The work: armed with hard numbers, a laptop and drill bits i set off to teaching myself some sheet metal design to make a lil platform to hook around the bellhousing and wedge between the engine block and trans, a local fab shop did the laser cutting and bending work for me and so it was time to test fit, cut and drill stuff.
The sheet metal bracket
Drilling holes in my new...used AX15 and chopping up the clutch dust plate to fit the adapter in
Test fitting the crank sensor
Apparently the 42RLE trans mount bracket is VERY different from the manuals....and i found this out the hard way when i tried installing it all and almost crushed my precious crank sensor, tried for days to find one off of an NSG knowing that with my tummy tuck in i was locked into the late model transmission mount geometry....but alas i couldn't find one and the ones i found on ebay just were not worth shipping over (enjoy some "not the NSG mount photos") so i made my own from measurements off of an AX15 mount and photos of the NSG backet compared to the mount bushing that sits between the trans and skid plate. If you're wondering, why you cant use the 42rle bracket in this case, the bolt pattern on the transmission is different, the distance from said bolt pattern to the mount is different both longitudinally and vertically whereas the manuals were all relatively similar and the bolt pattern on the transmissions all matched.
Butchered my 42RLE mount before realizing it wasnt gonna fit anyway
Darn transmission mount bracket....3D scanned my 42RLE bracket and the AX15 bracket using an android app, used a local coin to help me match the scale in CAD
AND THE FINAL PRODUCT
I dont wanna buy trans tunnel parts: i made my own adapter plate to bolt an AX inner boot to the 42RLE tunnel bracket, boot pending but fitment is good.
Now im on a 3d scanning binge you see, so i 3D scanned my automatic shifter tunnel bezel thing to make an adapter for the Ax15 inner boot
BUT SHE WONT START! So i started with just tricking the TCM into thinking it was always in neutral....a couple of wires here and there and a connector pinout for the neutral/park safety switch form the very handy FSM posted here on the forum and i managed a bodge and she starts!
Now she wont rev past 3000 rpm which is a problem in a sport where we regularly bounce off the redline, in comes HP tuners! my friend the fixes TJs...well the owner of the land his shop is on dabbles in messing around with his cars so he's got an MPVI2...perfect! Back to friend no.2's place to play around....we basically made a copy of his manual TJ PCM file and applied it all to mine.....Now she wont start again! turns out i dont have the clutch safety bits plumbed from the PCM to the firewall and we're lazy so now i've got a switch in the TJ that shorts the trigger pins on the starter relay i push switch while turning the key and bingo she starts!
Some photos and videos of her starting with TCM bodge and with weird dual switch thinger....and her first drive where the exhaust gases famn near burnt a hole in my thigh
Depinning a scrap harness to pin connector C3 from the PCM to clutch safety is on the table now, OR hear me out here....reactivate the TCM and run my little NPSS bodge to the clutch, still undecided but either is better than needing 2 hands and 3 legs to start a car.
Cost analysis:
The long way, WITH PHOTOS!
I'm going to avoid talking about things that have already been discussed on the matter and just stick to what i think hasnt been talked about or at least what i havent seen talked about.
My goal was to not buy the Novak bell housing, not swap PCMs, learn some new skills, be a cheap bastard and best of all, sink some more blood sweat and tears into my TJ, i like my TJ, i dont want someone else's TJ that has a manual in it, mine runs well and has a bunch of cool stuff on it that almost no one else in this country has on theirs and i like it that way.
I live in the middle east, rock crawling isn't all that popular so i learned my driving in the desert, while i know most of you guys in the west prefer your TJs on the rocks, they've actually got some great features that make them great in the desert, and the way we navigate the dunes here on a technical standpoint has sorta evolved around the geometry of a solid axle vehicles; mind you, my assumptions are based on videos of Americans and Australians hitting up dunes, so i might be a tad ignorant on the west's techniques.
The issue: we drive around at fairly high speeds compared to rock crawling and at relatively high RPMS, actually usually we're closer to redline than idle, so between the torque converter, the clutches, poor gearing and slippage you get in the 42RLE once you hit a certain skill level it starts to become a bit of a hinderance, not to mention that even with trans oil coolers the size of an AC condenser these 42RLEs just love overheating and begging for expensive rebuilds every 2 or 3 years (assuming you go out as often and as hard as i did.....spent a year with basically no 1st gear or Reverse because i just didnt wanna cough up the moola). So here's the goal: Manual trans swap for the cost of my last 42RLE rebuild invoice.
Below is a video of me in my automatic (2022, so around the time i lost reverse), barely keeping up with my friend in a very beat up NSG370, driving around in 4low because his TJ pops out of 1st and 2nd. Also a video of a friend of mine following a local club convoy...for context.
As i've reached my daily youtube upload limit..... https://drive.google.com/file/d/1BLlZOu3fWkKbz7Eh-F8IREOZWar4zC1s/view?usp=sharing
It cost me AED6200 (tax included) to rebuild my 42RLE on it's 3rd and final rebuild) which is $1,688 circa. August 2023.
The thinking: the Novak adapter is basically just a flat face for the late model sensor to sit on with a threaded hole with extra steps because making cool products is cool....so what if i make a hole in an AX15 bell housing and then make a mount of some sort to adapt it.
So i'm lucky here, i have amazing friends, a friend who fixes TJs for a living happened to have a broken NSG laying around that i pulled the bellhousing off of and another friend with a spare AX15 that i pulled the bellhousing off of as well...we went back to friend no.2's place and we took some measurements to compare, a few 3D prints, some adjustments and about 4 hours later we know where the hole is meant to go relative to the input shaft.
Designing with my friend Mermaid
AX15s are a dime a dozen at scrap yards here so that was my smallest hurdle
The work: armed with hard numbers, a laptop and drill bits i set off to teaching myself some sheet metal design to make a lil platform to hook around the bellhousing and wedge between the engine block and trans, a local fab shop did the laser cutting and bending work for me and so it was time to test fit, cut and drill stuff.
The sheet metal bracket
Drilling holes in my new...used AX15 and chopping up the clutch dust plate to fit the adapter in
Test fitting the crank sensor
Apparently the 42RLE trans mount bracket is VERY different from the manuals....and i found this out the hard way when i tried installing it all and almost crushed my precious crank sensor, tried for days to find one off of an NSG knowing that with my tummy tuck in i was locked into the late model transmission mount geometry....but alas i couldn't find one and the ones i found on ebay just were not worth shipping over (enjoy some "not the NSG mount photos") so i made my own from measurements off of an AX15 mount and photos of the NSG backet compared to the mount bushing that sits between the trans and skid plate. If you're wondering, why you cant use the 42rle bracket in this case, the bolt pattern on the transmission is different, the distance from said bolt pattern to the mount is different both longitudinally and vertically whereas the manuals were all relatively similar and the bolt pattern on the transmissions all matched.
Butchered my 42RLE mount before realizing it wasnt gonna fit anyway
Darn transmission mount bracket....3D scanned my 42RLE bracket and the AX15 bracket using an android app, used a local coin to help me match the scale in CAD
AND THE FINAL PRODUCT
I dont wanna buy trans tunnel parts: i made my own adapter plate to bolt an AX inner boot to the 42RLE tunnel bracket, boot pending but fitment is good.
Now im on a 3d scanning binge you see, so i 3D scanned my automatic shifter tunnel bezel thing to make an adapter for the Ax15 inner boot
BUT SHE WONT START! So i started with just tricking the TCM into thinking it was always in neutral....a couple of wires here and there and a connector pinout for the neutral/park safety switch form the very handy FSM posted here on the forum and i managed a bodge and she starts!
Now she wont rev past 3000 rpm which is a problem in a sport where we regularly bounce off the redline, in comes HP tuners! my friend the fixes TJs...well the owner of the land his shop is on dabbles in messing around with his cars so he's got an MPVI2...perfect! Back to friend no.2's place to play around....we basically made a copy of his manual TJ PCM file and applied it all to mine.....Now she wont start again! turns out i dont have the clutch safety bits plumbed from the PCM to the firewall and we're lazy so now i've got a switch in the TJ that shorts the trigger pins on the starter relay i push switch while turning the key and bingo she starts!
Some photos and videos of her starting with TCM bodge and with weird dual switch thinger....and her first drive where the exhaust gases famn near burnt a hole in my thigh
Depinning a scrap harness to pin connector C3 from the PCM to clutch safety is on the table now, OR hear me out here....reactivate the TCM and run my little NPSS bodge to the clutch, still undecided but either is better than needing 2 hands and 3 legs to start a car.
Cost analysis:
- Used AX15 from a scrap yard (critically, with an AX15 clutch cover plate) - $653
- Flywheel - Free from a friend
- Luk clutch bits - $185
- Clutch master and slave cylinder - $191
- DIY crank sensor adapter - $14 (not counting the cost of design labour or the multiple test pieces made)
- DIY trans mount bracket - $54
- New hardware and such - $10
- New starter - $30
- ARP flywheel bolts - $40
- HP tuners credits - $100
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