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  Topic Review (Newest First)
01-07-2020 08:59 PM
CatSplat
Quote:
Originally Posted by variable View Post
This is a semi-daily driver (I alternate with a car depending on when parking enforcement last checked on things...)

Last few times I've gone wheeling I've ended up in 4LO for a good chunk of the time, but with 33's and the 3.73 gear ratio, I suspect the 4x4 setting will tilt more towards 4HI when I get around to putting 4.10's in.

I wanted to spend more time in 2HI, but I had very mixed luck getting it to actually stay in 2HI. Even when I had the 242 pulled apart and was playing around with it on the bench, it seemed like 2HI was marginally better than full time - front and rear would spin by hand in 2HI unless I put a fair amount of resistance on the front shaft to stop it, so it seemed like there might be some waste there - if just in weight.

It sounds like I'm probably better off keeping the 249 with the 5.9. I *might* have the original bits to put the 249 for the 5.2 back together, but I wasn't anticipating this so.. I may need to get creative.. (who needs a transfer case anyway!)

One other thing that caught my eye is that it looks like the 46RE in the 5.9 may be shorter than the 46RH in the 5.2 (93). I've got an SYE on the 242 (hack n tap) but I'm not actually sure what the reach is of the telescoping driveshaft I have (it may have its own issues - I can't extend or compress it by hand for some reason). This also makes me curious about the pinion angle and driveshaft length of the front end as this would (I think?) bring the t-case forward a bit? Probably over-thinking it.

2WD doesn't do anything for efficiency on our vehicles, the front output gets back-driven by the front axle anyway. I find that 2WD is nice just for lighter steering, but there's not much in the way of advantages for that mode. Well, apart from snowy parking lot drifts.


I agree there's nothing wrong with keeping the 249 if it's in good shape and the VC works.


Yes, the 46RE is shorter (by a couple of inches) than the 46RH due to a different design of the overdrive housing. Accordingly, it requires a slightly longer rear drive shaft as the TC is indeed further forward than on the 46RH ZJs. If you're using anything apart from a factory 5.9 drive shaft back there, you will need a 1310-1330 conversion U-joint at the axle end as the 5.9 was the only ZJ to use a 1330 rear axle yoke.
01-07-2020 06:40 PM
PolkaPower I wouldn't bother swapping the 249 unless it's got a bad viscous coupler.
It's basically rwd until it slips and operates in 4lo just like the rest of them.

Sent from my BND-L24 using Tapatalk
01-07-2020 06:19 PM
variable
Quote:
Originally Posted by CatSplat View Post
I personally prefer the 242, but if you wheel in 4LO rather than 4HI the 249 is just as capable as the 242 and is unquestionably the stronger case. I spend a lot of time in 2HI so I opted for the 242 (coming from an early 249). The 249 is a better case for mixed-condition street driving (rain, snow) if that is important to you. If this is a trail-only rig, the 231 has better ground clearance but you lose a full-time 4WD option.
This is a semi-daily driver (I alternate with a car depending on when parking enforcement last checked on things...)

Last few times I've gone wheeling I've ended up in 4LO for a good chunk of the time, but with 33's and the 3.73 gear ratio, I suspect the 4x4 setting will tilt more towards 4HI when I get around to putting 4.10's in.

I wanted to spend more time in 2HI, but I had very mixed luck getting it to actually stay in 2HI. Even when I had the 242 pulled apart and was playing around with it on the bench, it seemed like 2HI was marginally better than full time - front and rear would spin by hand in 2HI unless I put a fair amount of resistance on the front shaft to stop it, so it seemed like there might be some waste there - if just in weight.

It sounds like I'm probably better off keeping the 249 with the 5.9. I *might* have the original bits to put the 249 for the 5.2 back together, but I wasn't anticipating this so.. I may need to get creative.. (who needs a transfer case anyway!)

One other thing that caught my eye is that it looks like the 46RE in the 5.9 may be shorter than the 46RH in the 5.2 (93). I've got an SYE on the 242 (hack n tap) but I'm not actually sure what the reach is of the telescoping driveshaft I have (it may have its own issues - I can't extend or compress it by hand for some reason). This also makes me curious about the pinion angle and driveshaft length of the front end as this would (I think?) bring the t-case forward a bit? Probably over-thinking it.
01-07-2020 06:07 PM
CatSplat
Quote:
Originally Posted by variable View Post
Hopefully I'm not hijacking - looks like the last post was just far enough back

I've got a 93 with the 5.2 and I've done the front case swap for the np242 (btw, 2wd is a useless piece of...) I've got enough things on my to do list that finding a 98 5.9 for $1500 is quite a bit more worth the trouble than upgrading all the crap on the 93.

In case you hadn't already guessed, I'm contemplating what to do with the transfer case(s) if I buy it. I'll have the NV249 which as I understand it solves the 4 low problem that the earlier years had with the NP249 (i.e. it doesn't lock front-rear). From what I've been able to glean, the 242 is still a better transfer case... except that now its not going to just bolt up, I'll need to dig out the old parts and put it back - I'll have to dig around to see what the length of the input shaft is (I think its the longer one? All I remember is that it needed swapping)

Short of it being - is the new(ish) 249 worth keeping on there or should I put the effort into swapping the 242 over? I've got 33x12.5 with >6" lift (I think... I stupidly didn't take a good measurement of things before and after.. long story)

I'm not entirely convinced that I got the 242 put together quite "right" - there's some play when putting it in gear to the extent that I her a nice klunk from the driveline, but one problem at a time.

So.. NV249 (from 98) or NP242 (with 249 front case)?

(Completely unrelated - did I read right that the 5.9 needs premium gas?)
You've got things basically correct. You swapped the case half to your '93 to get the long input shaft (and presumably avoid a gear cut problem, since you did the case-half instead of just the input swap). So to use that case (which I assume is '96 or newer) on the 5.9 you will need to basically take it back to stock and make sure it has the right input length for the 5.9. If you're unsure of the case's gear cut or input length (or just can't find all the old parts) you can also use the 5.9 front case half.

I personally prefer the 242, but if you wheel in 4LO rather than 4HI the 249 is just as capable as the 242 and is unquestionably the stronger case. I spend a lot of time in 2HI so I opted for the 242 (coming from an early 249). The 249 is a better case for mixed-condition street driving (rain, snow) if that is important to you. If this is a trail-only rig, the 231 has better ground clearance but you lose a full-time 4WD option.

Yes, unless the computer has been re-flashed with the infamous "death tune", the 5.9 requires premium gas to avoid spark knock. It's internally identical to the Dodge truck motors, but in Jeep form they gave it more aggressive spark timing for extra power.
01-07-2020 04:33 PM
variable Hopefully I'm not hijacking - looks like the last post was just far enough back

I've got a 93 with the 5.2 and I've done the front case swap for the np242 (btw, 2wd is a useless piece of...) I've got enough things on my to do list that finding a 98 5.9 for $1500 is quite a bit more worth the trouble than upgrading all the crap on the 93.

In case you hadn't already guessed, I'm contemplating what to do with the transfer case(s) if I buy it. I'll have the NV249 which as I understand it solves the 4 low problem that the earlier years had with the NP249 (i.e. it doesn't lock front-rear). From what I've been able to glean, the 242 is still a better transfer case... except that now its not going to just bolt up, I'll need to dig out the old parts and put it back - I'll have to dig around to see what the length of the input shaft is (I think its the longer one? All I remember is that it needed swapping)

Short of it being - is the new(ish) 249 worth keeping on there or should I put the effort into swapping the 242 over? I've got 33x12.5 with >6" lift (I think... I stupidly didn't take a good measurement of things before and after.. long story)

I'm not entirely convinced that I got the 242 put together quite "right" - there's some play when putting it in gear to the extent that I her a nice klunk from the driveline, but one problem at a time.

So.. NV249 (from 98) or NP242 (with 249 front case)?

(Completely unrelated - did I read right that the 5.9 needs premium gas?)
12-11-2019 02:07 PM
PolkaPower
Quote:
Originally Posted by chanaum View Post
hello i am french and i speak and write a little english.I have a NP 249 transfert case;This B.T. is not on the car.Is that possible to see when the car not run if the VC is good or bad.?
You cannot tell the condition of a VC not installed on the vehicle.

Sent from my BND-L24 using Tapatalk
12-11-2019 01:55 PM
riverzj
Quote:
Originally Posted by chanaum View Post
hello i am french and i speak and write a little english.I have a NP 249 transfert case;This B.T. is not on the car.Is that possible to see when the car not run if the VC is good or bad.?


I donít have an answer to this question. But to the english speakers on the forum, Iím assuming he wants to know if you can check to see if a VC is good or not with the transfercase removed from the vehicle.


Sent from my iPhone using Tapatalk
12-11-2019 01:47 PM
chanaum hello i am french and i speak and write a little english.I have a NP 249 transfert case;This B.T. is not on the car.Is that possible to see when the car not run if the VC is good or bad.?
12-09-2019 04:22 PM
terpsmandan And no leaks out of a used transfer case that had been sitting for 10 years. Also ironic that I looked around FB and CL and now that I am done, I cannot find a used T-case, and I had the 231 that I swapped in was delivered to me at work for $100... Sometimes Karma is is good.....
11-30-2019 01:52 PM
kg6mov All ZJ/XJ/MJ/YJ/TJ front shaft u-joints are the same 1310's.

That sounds like it'd be about the right length if you're measuring correctly.
11-30-2019 01:44 PM
terpsmandan
Quote:
Originally Posted by SoCalJeep4x4 View Post
I swapped a 242 into my project 96 ZJ. MY ZJ came with no front drive shaft and now I need to find one that will fit. Both the tc and differential have u joint yolks and measures 31Ē from center of yolk to center of yolk. Any idea of what ds may fit?


Edit: I found a drive shaft on ebay I think will work. It is for an XJ and measures
Extended Length: 33 inch
Over Compressed Length: 30.7 inch

https://www.ebay.com/itm/383105602653

Do you guys think this will work?
It should, but before purchase, I would verify that your Dana 30 has the same size yoke as the Dana 30 in a 93. Also I would be curious to see why the AW4 is the only compatible transmission.
11-29-2019 08:44 PM
SoCalJeep4x4 I swapped a 242 into my project 96 ZJ. MY ZJ came with no front drive shaft and now I need to find one that will fit. Both the tc and differential have u joint yolks and measures 31” from center of yolk to center of yolk. Any idea of what ds may fit?


Edit: I found a drive shaft on ebay I think will work. It is for an XJ and measures
Extended Length: 33 inch
Over Compressed Length: 30.7 inch

https://www.ebay.com/itm/383105602653

Do you guys think this will work?
11-15-2019 07:53 AM
terpsmandan And it's done. It goes all the way into 4lo. Still have to swap the plugs in the VIC and it's a little stiff coming out of 4lo but it all works. This is a great thread.
11-14-2019 04:14 PM
terpsmandan
Quote:
Originally Posted by PolkaPower View Post
Plate to handle? I swapped the entire shifter assembly from the 4.0 242 in. It was a little tedious but not terrible. Only took twice to adjust it until it worked great.

Sent from my BND-L24 using Tapatalk
I need to proofread.... I was concerned about getting the part that attaches to the shift lever. Probably not bad once you get the OEM linkage out of the way.
11-14-2019 03:29 PM
PolkaPower
Quote:
Originally Posted by terpsmandan View Post
Was it difficult to get the plate to handle installed or was it easier once you get the rest of the crap out of way?
Plate to handle? I swapped the entire shifter assembly from the 4.0 242 in. It was a little tedious but not terrible. Only took twice to adjust it until it worked great.

Sent from my BND-L24 using Tapatalk
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