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Discussion Starter · #1 ·
My 01 WJ is fairly new to me and is the first jeep I've owned w/ the 242 tc (select-trac). I've had a CJ w/ a d300, a ZJ w/ a 249 and my willys has a D18, so I know how those work.
Does the 242 have a clutch pack or viscous coupler in it like the 249, or is is completely open when in 4 full time? I know it locks when put in 4 hi-part time, but I cant figure out 4 hi-full time. It doesnt really feel like the 249 in my old ZJ, but the coupler was shot and pretty much locked up all the time. It was pretty easy to put it into a 4 wheel drift when on snow/ice. My WJ doesnt seem to do that as easily.
 

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Its not a viscous coupling. I didn't know the best way to describe it, so I did some quick Googling and its a torque-biasing differential.

I say again - quick Googling. :teehee:

Found this: http://www.novak-adapt.com/knowledge/np242.htm
 

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Discussion Starter · #3 ·
well, I did google first and came up w/ the same basic info. so far all I've learned is the same term you learned by doing the same. So, what is "torque based differential"?
I see it's a 48/52 split, But does it vary? Does it limit slip or let the loose wheel spin freely? Is it a clutch pack, or a fluid based mechinism? Will it eventually wear out w/ too much dry pavement use?

I'm just curious and wondering if anyone w/ some first hand REAL :poke: knowledge can give me some insight.
 

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From my understanding it is similar to a open diff in a axle with spider gears and such, so just like a open diff it will send all the power to the axle with the least amount of traction were the 247/249 the viscous coupler acts more like a limited slip diff.
 

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well, I did google first and came up w/ the same basic info. so far all I've learned is the same term you learned by doing the same. So, what is "torque based differential"?
I see it's a 48/52 split, But does it vary? Does it limit slip or let the loose wheel spin freely? Is it a clutch pack, or a fluid based mechinism? Will it eventually wear out w/ too much dry pavement use?

I'm just curious and wondering if anyone w/ some first hand REAL :poke: knowledge can give me some insight.
Then Google more. :sonicjay: After doing another 10 seconds of GOOGLING, I found this:

http://www.jeep4x4center.com/jeep-transfer-case/np-242-parts.htm

And this:

http://books.google.com/books?id=X9...X&oi=book_result&resnum=4&ct=result#PPA108,M1

Its a mechanically biased differential. No clutches. Not a fluid coupling. If it varied, it wouldn't be a 48/52 split. Its a "dumb" transfer case that doesn't make any decisions and all it does is send 48% of the torque to the front driveshaft and 52% to the rear in Full-time mode. Yes, it can eventually wear out from extended dry pavement use, but not as fast as a true part-time case. It has no control over any individual wheel. If your vehicle does have other controls, you don't have a 242 and its either a Quadra-Trac II or a Quadra-Drive system.
 

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Discussion Starter · #6 ·
Thanks for sharing your google expertise.

It's just the 242 select-trac case. I wonder how it would do paired w/ the vari-lock axles from a quadra-drive system ....
 

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Thanks for sharing your google expertise.

It's just the 242 select-trac case. I wonder how it would do paired w/ the vari-lock axles from a quadra-drive system ....
If you check that second link and read about that system, you'll see what it will and will not do compared to the transfer cases that come in Quadra-Trac II and Quadra-Drive vehicles.:thumb:
 
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