Retrofit 5 speed into a Select Trac XJ?

[Root Moose]

Has anyone ever done this? Just wondering how the five speed (Aisin or NV) works with Select Trac.

I remember reading somewhere that Jeep didn't make this combo available because of driveline slop in this combination with the 5 speed and the full-time mode.

I read it on a forum somewhere so it could be complete and total BS - forget where - probalby JU. :)

r@m

[woody]

I don't think a manual trans would have more slop than an auto (especially one that has the torque convertor locking and unlocking on it's own schedule) I'd think -with the clutch out-it would have less slop. (assuming a certain/similar amount of TC chain windup that would exist with either tranny...)

As to why Jeep never offered it? I'd suspect it's because the 242 was usually offered on the up-market XJs, and most folks in that market tend choose an auto.

I'd also suspect that a 242 in "full-time" mode would work fine behind a 5-speed in a similar role as normally seen behind the AW4. (used on mixed/slippery roads- either all the time or on-demand) I don't think a 242 would stay happy having the crap beat out of it regularly - ie: Lots of full throttle AWD pavement launches :viking: with either tranny, but maybe it would? Lots of other little loose ends that sort of duty would shed light on.

I am surprised no one has done this swap that can post up the + and - from their experience.

[MrShoeBoy]

I would LOVE to have the AWD option offered by the 242. I have major traction issues with an open rear and the power from the stroker motor. Something tells me that my driving style, a BUILT 4.6L stroker, and AWD Pavement launches wouldnt mix. I like to race :D

I also already have a 231 with a 2lo kit and AA HD SYE and driveshaft so it would really be expensive for me to go the 242 route.

If you do go with the manual and 242 post up the results so we know how it works and dont have to speculate

AARON

[cLAYH]

I had a NP242 behind my Peugot 5spd for awhile. Had to replace the worn out 231 and 242 are cheap here.

Worked fine except that sometimes when braking on a slippery surface with the clutch in and the case in Full-Time 4WD(AWD) there would be a loud banging coming from the drivetrain. Not quite sure where. I had a rear lockright so that may have had something to do with it as well.

Now I've replaced the 5spd with an AW4, same t-case and diffs, locker, tires and have not had the same reaction when the brakes lock up on icy surfaces.

[RichP]

Rumour has it that the 242 won't stand up to the direct torque of the 5 speed. Might also have had something to do with liability. Ever notice that the autos have a higher tow rating than the 5 speeds do. This also is something I have considered and one of the reasons I've kept my eyes open for cheap and handy 242... I also seem to remember something about the drive shaft has to shortened a couple of inches

[CheapXJ]

dunno 'bout the nv tranny, but a 242 works just fine behind an ax15.

nothing needs done to the driveshafts or shift linkage to put it on. it's literally a bolt on swap (gotta mess with some wiring to make the full time light work, but that's really no big deal)

and the swap has been done.

want more details, pm stoneattic about it. he drives his 242 equipped 4.0L/5-speed XJ everyday (and loves it :D )

[RichP]

Forgot the other part, ketjar has done the auto to 5 speed conversion when he had to swap bodies, he went from I think a 98 to a 97, I dont think he went 242 though, think he stayed with his 231. The full time light drove someone else nuts for a few days till they finally got a pigtail if I remember right , that would hookup and fire off the full time bulb. But if I understand you correctly you want to pull your AW4 out and put an AX-15 in there. It has been done a few times here and I dont remember hearing any problems or 'wish I had not done it' posts.. DC though did have a reason for not offering it and while it might have had something to do with marketing I remember way back when this came up a few years ago that there were some other issues involved...there should be alot of material if you do a search.

[Root Moose]

I guess I should add why I'm asking this.

Close friend of mine is thinking about getting an XJ. He's a stick kind of guy, and he also wants the NV242 for the full-time mode.

So, he doesn't currently own an XJ. Given that, which way do you think he should go to get a 5 speed and an NV242?

My inital thought is that he should find a 5 speed XJ (seems quite rare locally), and buy a 242 to add on to it. Between the buy/sell pricing he may even make a few bucks off of selling the 231 and buying a 242. 242s are normally quite a bit cheaper.

There's always buying a AW4 XJ and swapping the tranny, but I'd guess that would be much more expensive and time consuming.

What year was the change from AX-15 to NV35x0? 1997+? They are pretty much the same wrt strength, ratios, feeel, etc. right? One doesn't have a real advantage over the other? I'm an AW4 guy so I don't know much about the manual tranny side of XJs.

Or, is there a better option? If he went the custom tranny route is there anything out there that can be swapped in with a lower first gear? I hear the new TJ tranny (NV5600?) has a ~4:1 first but that is a lot of money/time for a marginal increase.

Swapping/changing driveshafts is no big deal, a CV shaft on the back will be added anyway.

Options/opinions?

r@m

[explorer]

Swapping the case would be much easier than swapping the trans. Not that its that difficult. As far as the grind boxes, finding an NV3550 or whatever the new TJ trans is would be great. It wasn't used till '01 I think, I didn't ever see one in an XJ. The NV3550 shifts much easier. My AX15 is hard to shift regardless of temp, fluid, etc. The NV can be shifted into 1st going 25-30 mph w/ little pressure on the lever. While this might not be great for the life of the synchros, it shows that they work extrememly well. I sometimes worry about bending the lever on my AX15 when its cold for comparison. The NV5600 is a heavy duty(truck) 6 spd. used in 3/4 or 1 ton trucks. I left the dealer before the 6spd Jeep trans came out, so I don't know what the model # is. But the 1st gear ratio is around 4.5 or 4.6:1. The AX's are @4:1. Aside from the 10%+ lower first, you get closer spaced gears for more options.

[cLAYH]

I swapped a NP242 into my XJ and then a year later converted it from a 5spd to an automatic. So you can guess what my opinion is. Just buy an automatic and enjoy it!

[scoobyxj]

While you would lose the two wheel drive. You might get a 249 from a ZJ. Although I dont think they last as long between rebuilds with the viscous coupling.

[Root Moose]

NV249 is definately not an option (VC, 2wd is required).

r@m

[XJJack]

dunno 'bout the nv tranny, but a 242 works just fine behind an ax15.

nothing needs done to the driveshafts or shift linkage to put it on. it's literally a bolt on swap (gotta mess with some wiring to make the full time light work, but that's really no big deal)

and the swap has been done.

want more details, pm stoneattic about it. he drives his 242 equipped 4.0L/5-speed XJ everyday (and loves it :D )


What do you mean mess with the wiring? I have a 242 in my 98 that I took out of my 89 and can not find the wiring to make the full time light work, please tell me how you did this.

[CheapXJ]

98 wiring is way different. you'll prolly need the indicator switch from a 97+ 242.

go junkyard researching. find one and trace the wires to see where they go.

[rockwerks]

98 wiring is way different. you'll prolly need the indicator switch from a 97+ 242.

go junkyard researching. find one and trace the wires to see where they go.

HMMM a 6 pack and a beach chair a great hobby!