Transfer case options.....

ghost

ghost

Well-Known Member
Joined
May 25, 2006
Location
Hartsville/Camden,SC
Ok I currently wheel a 94 xj chopped and beat on xj with an AW-4 203/205 D60's and 42" SXII's. I'm going to be getting a 96 5 speed xj that is chopped and a better built cage. Trying to deiced a direction on the transfer case. I love the strength of the 203/205 but not the fact that they are 1.98:1 low ranges and to flat belly an xj you loose a lot of room for seat mounts. I'm probably going to switch to the North West Fab Black box eventually in front of the 205 maybe. The new jeep has a 231 in it stuck in low range. Looking for options besides Atlas that are reasonable to put behind the Black Box. Not interested in a 300 for 2 reasons. They need to be flipped and they are not as strong as people think they are until you upgrade everything. That all being said who has run a dual transfer case set up with no breakage? What options are there for t cases besides the 205 for shear strength on a budget in a dual set up? Would really like to hear from people with real world experience.
 
Atlas is $2600

D300 is $1500 ish to buy and for 4:1s and HD outputs, not including to flip it.

Not sure any other case that gets gearing close to either that is much cheaper, or weighs less or comparable in strength.

203/205 you have to spend $800 for cases and doubler, and it is pretty long and super heavy.

My guess would be to spend $1k on a 241 from a rubicon if you are opposed to a 300.
 
X2 on rubi 241. I helped with an install recently and I can tell you a 241 is no joke. 32 spline outputs F/r.
 
I run the 203/205 now. I think I have about $800 total in that set up. Maybe $1K. I wish Lomax would make a low gear set for the Ford 205...... I saw an eBay auction recently on the 241 and it was less than $1K. So the 241 is a decent case. Are all the Jeep 241's 23 spline input and will bolt up to an ax-15?
 
ghost said:
I run the 203/205 now. I think I have about $800 total in that set up. Maybe $1K. I wish Lomax would make a low gear set for the Ford 205...... I saw an eBay auction recently on the 241 and it was less than $1K. So the 241 is a decent case. Are all the Jeep 241's 23 spline input and will bolt up to an ax-15?
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Yes it will. Direct bolt in.
Worth it to mention, you will need to shorten or lengthen driveshafts though.
 
XJsavage said:
Yes it will. Direct bolt in.
Worth it to mention, you will need to shorten or lengthen driveshafts though.
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Yea I figured that. Anyone have a crawl box in front of one of these? Or know of someone that does?
 
Mac5005 said:
The rubicon 241 should be 4:1 low range, are you trying to gear deeper than 4:1, or have option of 2.72 and 4.1,and double low?
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With the 203/205 I have a 1.98:1 and a 3.98:1 now. The 1.98 is a little light at times and the 3.98:1 is a little deep. So yea I would like the 2.72 and 4:1 and double low option I think. Just looking to see what options are and suggestions info on people with real world experience. I think I read about a low range box that replaces the transmission output case not long ago.
 
Do you really want to double a chain drive t-case?
Sounds like a horrible idea.
 
I'm runnin a 241/205 doubler in a locked 1 ton blazer w 42's and have had zero issues.
 
NickMaul said:
This is all I am aware of at the moment of a tailhousing replacement.

Rubi-Crawler : Rubi-Crawler Auxillary Crawl Box For 42RLE Transmission | Advance Adapters

No real life experience but I have read enough build stories were an atlas saves money in the long run. Kind of like the dana 44 vs dana 60 argument.
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Good friend of mine has one in his TJ with a 231 in it. It's low as hell but worked great out west. Personally I'm going with a 241/205 doubler in my k5, and eventually I'll do a 231/300 in my JK. I wouldn't want 2.72:1/4:1/10.88:1 or whatever it is. Wayyy to low even for west coast wheeling. 2.72/2.72/7.4:1 is plenty.

Edit: with an auto you're gonna push through your brakes so get use to shifting into neutral when you need to stop in low/low.
 
My personal experience from wheeling:

I have ax-15 with d300 with 4:1s and 5.38 in the axles with 42s.

My crawl ratios in low:

1st gear: 82:1
2nd gear: 50:1
3rd gear: 31:1
4th gear: 21:1

First gear is all but pointless in practical use on the trail. I can literally get out of jeep, and walk beside it when in this combo at idle. It's west coast cool to crawl stuff but that's it.

Typically I run almost 90% of trails and obstacles in 2nd gear.

Super hard stuff like little Jagger, middle Rock garden, the last ledge @ mason jar, anything hard that requires any kind of wheel speed, I use third gear and lots of throttle. Still low enough to be able to work the clutch and halfway crawl obstacles, but high enough to get some decent wheel speed.

The jeep does not like 4th gear on anything technical. Usually slips the clutch or bogs the motor.

All that said. If I had an auto, I would be shopping for 5.13s for the axles, or get rid of the 4:1s in the case. The torque converter effectively doubles your crawl ratio while crawling.

One reason it is superior in super technical stuff as you can low crawl ratio while getting decent wheel speed without shifting.

Aw4 with 4:1, 5.38s
1st: 60:1
2nd: 33:1

When you factor the torque multiplication of the auto this makes this setup super low, but doable. Also why then if running auto, it may be practical to have a 2.6 or 2.7 low range and work well. This would mean a stock d300 or 231/241.

My dads truck. Nothing special 454, 350/205, 5.13s, 42s. Crawl ratios:
1st gear: 25:1
2nd gear 15:1

We run all of the same trails but his converter means that all equals 2x those numbers. So we are back at that 50:1, and 30:1 range. Get the rpms up in 1st gear and that 50:1 turns back into 25:1 as the converter tries not to slip at all. Only time he uses 2nd gear is getting silly with the throttle.

My point to all that is work your ratios and see what is practical. It also somewhat depends on engine as well.

There is a sweet spot from 60:1 to 30:1. This isn't the west coast with high traction everywhere that you can crawl everything.

Obviously need lower ratio for a smaller motor.

Just don't think you should spend a lot of money, focus, time on a gearing setup that you will wind up with too many choices that you rarely use.

Bang for the buck your money would be better spend on bead locks, a winch, or shock tuning.
 
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Ok I have run all those trails with this set up. Biggest problem is the fact that with a 203/205 set up low is almost perfect but some times its not low enough to get my 42's moving. Double low and it's on the rev limiter. I know I'll eventually go with a black box 2.72:1 with a 205. I was just curious what was available besides the 300. A waste of time and money IMHO I have 3 friends that have broken them behind 231 crawl boxes. I know I need more motor.....
 
My old cab truck had a C6 tranny and NP208 with 2.72:1 low range. I was running 42" tires with 4.88 gears in the axles. I found that ratio to be great for general trail riding, but not low enough on technical stuff, and sometimes too low on faster connector type trails. After breaking two NP208's I bought an Atlas 4sp with 1:1, 2:1, 2.72:1, and 5.44:1 ratios. I loved those gearing options. You can get the same ratio options with the Black box and an NP205. That is what I would recommend.
 
drkelly said:
My old cab truck had a C6 tranny and NP208 with 2.72:1 low range. I was running 42" tires with 4.88 gears in the axles. I found that ratio to be great for general trail riding, but not low enough on technical stuff, and sometimes too low on faster connector type trails. After breaking two NP208's I bought an Atlas 4sp with 1:1, 2:1, 2.72:1, and 5.44:1 ratios. I loved those gearing options. You can get the same ratio options with the Black box and an NP205. That is what I would recommend.
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That is probably what will happen. Thanks for all the responses and suggestions.
 
NCJeeplover said:
I hate to bring up an old thread, but is there a diffrence between a tj and jk case? With either work?
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I know 2012-up automatic cases are different, regarding the inputs being male on the autos. I haven't sat 03-06 next to a 07-16 case though. There has been people using np208 and NP205 seals when going to 1350 CV yokes and stuff. I believe the rear one has to have the seal surface of the yoke turned down to the right diameter.
 
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