Np 231 Or Np 242 Transfer Case?

[mnkyboy]

So basically you understand how the parts work but not how they work together.

 

 

[cruiser54]

So basically you understand how the parts work but not how they work together.

 

Basically I've owned full time 4wds with lockers in them.

[mnkyboy]

What your saying is its ok to drive a jeep in full time on pavement with the front axle locked in.

 

 

 

 

[Geonovast]

What we're saying is it's no different than driving a Jeep in 2wd with the front axle locked - which people do.

[mnkyboy]

But it is.

 

When you are in full time you are supplying power to the front axle which will lock an autolocker so any time you are in full time the axle is locked. This defeats the purpose of the full time for street use which is the main reason people swap in a 242 in the first place.

 

 

[Bounty Hunter]

I agree with mnkyboy, I wouldn't want power to the front axle in fulltime 4wd with a front auto locker. You're asking for trouble trying to turn on pavement in a high-traction situation when on the throttle. You want the front unlocked on pavement, which is impossible when accelerating in 4wd fulltime.

[cruiser54]

What your saying is its ok to drive a jeep in full time on pavement with the front axle locked in.

 

This is not clear.

But it is.

 

When you are in full time you are supplying power to the front axle which will lock an autolocker so any time you are in full time the axle is locked. This defeats the purpose of the full time for street use which is the main reason people swap in a 242 in the first place.

 

This is. Shoulda been more clear in the first place, I guess.

[mnkyboy]

If you apply power to an axle with an autolocker it will lock. The point of full time is you can use it on the road, you don't want to be driving down the street with your front locker engaged.

 

I was

[earl*t]

This has been an entertaining exchange. I came up empty a quick search for the rubicon transfer case. I've read that it offers a 4:1 ratio and it will interchange. Would it be a viable swap? :dunno:

[mnkyboy]

Ive heard of people doing it. You can also build the 231 case to have the stronger parts and the 4.1:1 as well as a 2wd low range if you wanted.

 

You can beef the 242 up as well but there is less options out there then there is for the 231

[JeepcoMJ]

The factory limited slip in my xj grabs HARD. I put minimal mopar trac loc additive in it because I wanted it to do just that. The result, it functions as a clutch type auto locker. I have yet to see any adverse effects from this.

 

Removing differential function from either axle in no way effects the ability of the differential in the transfercase to differentiate speeds between the front and rear driveshafts. It can't, and won't.

 

Mnkyboy, you seem to have a skewed grasp on just what a differential does.

 

The only logical argument against running full time with a locker is that it could be considered akin to putting 35" tires on an open diff Dana 35. The question at that point is not IF it will brake, but HOW HARD do you have to push it to get it to do so. Daily driving shouldn't affect it, but doing a full time 360 drift in 6" of parking lot snow likely would not end very well with full time and auto lockers.

 

That said, full time in an np242 is directly intended for daily duty and light off road duty. If it were otherwise, you wouldn't have part time to choose from. The argument really comes down to driver error rather than the ability of the parts you bring up to work together under the driving style they were intended for.

 

Pat

[mnkyboy]

We are talking about the front not the rear, I doubt you have a limited slip in your d30.

 

And if you think my thinking is skewed then you obviously don't know how an autolocker works.

 

Driving in full time with an auto locker would be the same as driving in part time with one, which anybody with a brain knows you don't do on dry pavement.

 

You must have a selectable locker that can be turned off if you want to use full time on the road.

[mnkyboy]

Jeepco go weld your front spider gears and drive around for a while in full time then tell me whats skewed.

[JeepcoMJ]

You don't drive in dry pavement in part time. Period. I've got several broken in half np231s from customers to prove it.

 

And welding a front end....you will break axle shafts and unions turning before you will ever break the transfercase. The hopping caused by welded spiders going around corners would make sure of that. Anyone welding a Dana 30 at all is a complete idiot. I have done it once, after everyone told me not to. End result....7 sets of axleshafts later, I pulled the spiders and put originals back in, after some torch work.

 

an auto locker locks when there is fast variation between the left and right tires. That doesn't change the fact that the driveshaft spins. It will make the speed at which that front driveshaft spins more constant, which actually will make the parts in the transfercase work less, since the front and rear are more likely to remain similar in rotational speed. And again, you would blow up axleshafts before that stress would ever transfer to the transfercase.

 

The only danger then would be in fast acceleration while turning, with slippery conditions, which allow you to break loose the rear tires. Not a common situation, except in the case of driver error (or idiocy), or very very slippery snowy conditions....which you should be in part time for anyways. So yet again we come back down to driver error.

[mnkyboy]

Its not fast acceleration. Its super simple you apply power to it the locker locks you take power away it can ratchet.plain and simple.

 

When in full time you will be applying power to the front axle everytime you touch the gas which means you will be driving with the front locker locked which would be the same as driving with spider gears welded.

 

A locker is not a limited slip, when locked they act like a spool.

 

[JeepcoMJ]

You drive locked in any 4wd situation with a auto locker, so you argument still applies to driver error and has nothing to do with the transfer case.

[mnkyboy]

Do some looking on the web and you will find post after post saying exacty what ive been saying. I honestly thought it was common knowledge till today.

 

The only people you will find doing it don't use the full time function anymore or run with thier hubs unlocked on the street which isnt an option for us.

[Comanche County]

I know how a differential works because I watched this highly entertaining and instructive video. :rotf:

 

This has been an entertaining exchange. I came up empty a quick search for the rubicon transfer case. I've read that it offers a 4:1 ratio and it will interchange. Would it be a viable swap? :dunno:

 

I have one in my MJ. Bolted right in place of my old 231. They come with an SYE, but you'll need to either add a flange adapter to the front of your drive shaft or remove the flange and add a dana/spicer yoke to the back of the TC. You may need to shorten shorten or lengthen your drive shaft lengths. I don't remember how much, as I swapped in front and rear 44s at the same time. http://comancheclub.com/topic/22479-deep-in-the-heart-of-comanche-county/page__st__40

[mnkyboy]

You drive locked in any 4wd situation with a auto locker, so you argument still applies to driver error and has nothing to do with the transfer case.

 

Yes with a part time case but the point of the full time is to make it more like a subaru, people use it when its not necessary to be in part time.

[mnkyboy]

I run a 242 in my stock height 99 2door 5 speed xj. 3.07 gears, 245/70r16. Just in the last couple weeks, I towed an xj and a kj liberty on a tow dolly without trailer brakes...in full time 4wd the whole way. The Cherokee was 45 miles away, interstate travel and a bunch of stop and go traffic to get to the interstate and from it. The liberty was a bit further, and weighs over 1000lbs more than the xj I used to tow it with. I didn't have a single issue with either one, and the full time was necessary to plant the power to the ground on dry pavement...it also helped for slowing down via downshifting.

 

Was it a bit sketchy? Sure. I couldn't go over 65mph without a bit of trailer sway. But it did the job, and I could not have done it with an np231. I flat out love it for dd duty, tow duty, and envy thing else.

 

Guess I don't see the "weak point "

 

 

My point exactly. You didnt need full on 4wd so you used fulltime, how would this have played out if you had an autolocker.

[JeepcoMJ]

It would have played out just fine.

[mnkyboy]

In full time with a front autolocker towing ,the locker would have been locked most of your trip.

 

So you think you would have went all that way just fine with the front end locked?

 

 

[JeepcoMJ]

I can't come up with one single thing it would have negatively effected. Actually would have helped me keep the jeep straight on the freeway. Would have been tough to make hard turns, tho.

[mnkyboy]

Yes turning would have sucked,have you ever had one lock going around a corner? You drag a tire like a welded diff, not something you would want on a steer axle. They also can get bound up which would also suck on a steer axle.

 

I don't think people realize it but they are locked far more often then they are unlocked.

 

 

[Bounty Hunter]

It would have played out just fine.

Until you tried to turn under throttle. Mnkyboy isn't arguing the 242 is inherently weak or a bad choice, only that when used in Full-Time 4wd with a front automatic locker you will get horrible driving characteristics on dry pavement.

 

But what do I know, I've ran a welded d30 for years and now run spooled d44's on each end.