If I do the 4.1 kit does this eliminate the chain, and does it make the t case any stronger. Or should I do a flipped Dana 300.

You replace the front half of the tcase with a beefier looking unit with bigger planetaries. All other internals stay the same, including the chain and sprockets.
I dunno- for that thousand bucks you could be into the iron case, gear drive 300, sounds like a winner- but you still won't have deep gears.

I wouldn't dump any money into the 231. The front half of the case may be beefier on a Tera Low, but the rear half is still stock and supports the mainshaft and front shaft. I have just rebuilt one and the rear mainshaft bearing seat cracked right off along with the other internals eating $hit. I also have a cracked case off a donor that convinced me it's $hit!

... and I was riding in a Jeep where the 231 broke in half, at 70mph. But I still think they're a solid case, up to a point. I bet your busted one was run low on oil or the chain wadded, or whatever.
Now how many on this board have actually split one apart while wheeling would be cool to know.

Let me put it this way. MY 231 has let me down twice so far since 1997. And it has a heavy duty short shaft kit.
And a hole in it which was fixed with that metal puddy stuff.
And it has had a shifter fork replaced......

Need I say more.

Spend the money on a 300 flipped! You can teralow it too. But that's more cash.:grinpimp: :cow:

The busted case is the result of the front axle hitting a curb, pushing the driveshaft into the case and split it in half. The rebuilt unit had a retaining clip pop off the syncronizer hub and the syncronizer tabs fell off causing the gears to eat each other up. The internal pump also stripped out and cracked at the splines. I am sure the 4:1 kit is suitable for 35" tires and lower, but the torque multiplication and cast aluminum case makes me wonder about strength for hard use.

I must be the only one that's had good luck with them. Only ran 35's, though.
Now the NP242 is another story :flipoff: :mad: :nuke:

Quote from Insayn
"The busted case is the result of the front axle hitting a curb, pushing the driveshaft into the case and split it in half. "

Did thiss jeep have a shackle reversal were the front wheels travel rearward during compression?

I'm runnng another thread regarding a clunking noise on my YJ. The guys seem to think my NP231's chain is stretched and slapping the case. F*&%-=chains!!:mad3:

How much can you p/u a used 300 for and will it mate to an AX15?

Originally posted by DTC
If I do the 4.1 kit does this eliminate the chain, and does it make the t case any stronger. Or should I do a flipped Dana 300.

Before you spend all that money on a D300 Flip kit, check out the NP241. They came in '89 and later Chevy Pickups. They have a 6-gear planetary that's rated at more than double the torque capacity of a 231 planetary, a main shaft that is waaay thicker than a 231, a wider chain, and they are driver's side drop.

The bad news: You have to add the SYE, input gear, and possibly a new front output yoke (unless you can live with the Spicer flange and resultant front driveshaft length loss...) Still, the whole shebang ends up costing less than a D300 flip kit.

Jake

P.S.
I never had any trouble with my 231 either...
:flipoff2:

231's are junk.

i have blown 2 going 70mph down the interstate. and yes i had plenty of fluid in them both. all the bearings looked fine and all the internals looked fine also. they both broke in half between the front and rear driveshafts. im on my 3rd and final 231 right now! the only reason i keep replacing them is i get them for $200 easyyyy. just avoiding the $1k for the d300, flipped kit new driveshaftsssss

Originally posted by Slagburn
... and I was riding in a Jeep where the 231 broke in half, at 70mph. But I still think they're a solid case, up to a point. I bet your busted one was run low on oil or the chain wadded, or whatever.
Now how many on this board have actually split one apart while wheeling would be cool to know.

I broke one a couple weekends ago.

I broke one on the street, in my neighborhood... but it probably had a lot to do with me getting pissed off at my poorly running engine and dumping the clutch at full throttle (I was running 31's with 3.07 gears at the time). The case split on the lower rear half. Unfortunately I was young and uninformed and spent $1100 on a rebuild... oh well, gotta learn sometime.

I have one if you need a spare. The 231 was replaced with an Atlas II 4.3 to 1:D

Originally posted by DTC
If I do the 4.1 kit does this eliminate the chain, and does it make the t case any stronger. Or should I do a flipped Dana 300.

If you have to ask if it eliminates the chain and makes the case stronger... you really should be asking some other questions first.