IStoleIt

I have a 98 ZJ 5.2L with a 42re and NP249.
When i bought the Jeep it has roughly a 4" suspension lift kit(unknown make). unknown miles on the kit/suspension/steering.

Here soon i plan to refresh/upgrade the whole thing with adjustable: track bar, Upper and Lower Control arms, etc.
It will only be used for highway, mud, and trailing. No rock crawling for me! (OK. maybe a lil)

So i have searched here and at Mallcrawlin.com, and cant find any info about SYE's for my 249.
So either im just dumb or what???

What am i missing?
Should I just dump the 249 and swap in a 231?
What else do i need to do to stop the driveline vibrations?

Also i dont know the condition of my Viscous Coupler, and occasionally(cold engine) will slip a little from a stop. There are some vibrations/shakes for a just a second or two before it starts moving. After its warmed up there are no troubles.

I saw on a build thread where he had welded the VC together and says it has been running fine for a couple years. But this is the only instance of this i can find.
What are your thoughts on this?

Side note: i havent checked TC or Diff fluids, but the tranny fluid looks fine.

I know thats a few vague, open-ended questions, but i appreciate your feedback.

Thanks

dave1123

Usually when a VC goes bad, the front wheels will hop or skid when doing tight turns. Your slippage sounds more like the transmission. After the initial startup, shift to neutral for a few moments to allow the transmission to pressurize before you start out. If this makes a difference, your o-rings in the clutch packs are getting stiff and hard. If you weld up the VC, you'll be in part time 4wd all the time. Not good on pavement. Also, if you take the 249 apart to do that, you might as well do a swap to a 231 or 242. In either case, you'll have to match the t/case input shaft splines with the V8 transmission. You'll have to do the research, but I think the 249 input shaft will fit some of the other cases, depending on year and gear cut.

IStoleIt

Thanks. I'll try this.


My TC is Full time 4x4 (HI/LO) anyways. Whats the difference?


Ive done a Little research, and not much luck on 249 info. Tons on 231, and 242. It seems as though I just need to open mine and check.

Thanks

dave1123

The viscous clutch in the 249 allows slippage between the front and rear axle when turning. A welded clutch will not allow this. It would be like driving a 2wd with a welded differential.

I've been doing a bit of research myself on the SYE. It appears there is a conversion the requires a bolt hole be tapped in the end of the output shaft to hold the yoke solid and a slip-joint driveshaft used. As I've stated before, my 97 242 had a flange-mount tailshaft and the slip joint in the driveshaft so if you went with a t/case swap, you wouldn't have to worry about an SYE.

andrewmp6

Dave there is two kinds of a sye kit,One makes you open up the t case and change the shaft in it.The other is a hack and tap which you cut off part of the shaft and drill and tap the shaft.The hack and tap is easier to do and can be done to the jeep with the t case in.The other style you could do it with the t case in the jeep but its a nightmare to do it.

dave1123

Yes. I know, but never having done anything like this myself and not having eyes-on, I was just throwing out options. My intention was to get more informed people, like you, to chime in. My WJ is a DD and used in my business so I can't afford to screw it up by adding even a 2" BB, even though I'd like to. You have to be a masochist to have a jeep as your only transportation.

andrewmp6

You could buy a junkyard t case like yours to practice on,Or rebuild the same case add the sye and swap it in your jeep.

IStoleIt

This is exactly what i was thinking. Its probably the easiest and safest way to do this. I think my 249 works fine, or maybe my VC is slipping.

But a built TC on standby isnt a bad thing.

I'll probably attempt my own hack and tap then, after i get a 2nd working TC.


Anyone with the link to a step by step TC removal?

Thanks.

andrewmp6

This shows how to swap t cases but you can use the removal part http://kevinsoffroad.com/techarticle...-242_swap.html

SatiricalHen

Personally if I were you I would swap in a different transfer case if you're going to be getting a different one anyway.

Fred/N0AZZ

One thing you might consider is to PM XJ Wonders here and see what he gets for a used TC with the SYE installed he sells them and has for a long time in his spare time for members here. Can't hurt to find out what it would run I know he has different TC's available to install the SYE's in or can get them, he does use a good quality SYE also not the junk stuff.

IStoleIt

Thanks for the link! Great right up.

I will probably swap to a 242. It seems an easier swap than the 231.
But i guess it depends on what i find at the U-pull-it

dave1123

Yeah, I was going to mention that a new viscous clutch goes for between $300 and $400 so maybe a t/case swap is in order. You'll find the 231 in XJs and the 242 in ZJs. The 242J in the WJs don't have a speed sensor in them. (WJ=99-04 Grand Cherokee)

andrewmp6

If you do swap to a 242 you can upgrade the shifter linkage http://www.mountainvistafabrication....age-ZJ2421.htm