Atlas 5.0
This project is a long time a come'n.  I've planned and cancelled an Atlas at least 5 times before.  This time, I'm just going to get it over with.  My NP231 has held up fantastic over the years and is still in perfect shape.  It's got a 4:1, MIT SYE and a 2Lo.  Pretty well equiped, but lacks "front only" drive.  Also, the Atlas is an all steel case and is gear driven.  That is a heck of a lot stronger than the 231 and with the way I've been driving, I think I need the strength before I break something.  I found a buyer for the 231 so that will help offset the cost.

I did some math...  With the current setup (AX-15, 4:1, 4.88) I'm at 75:1 gear reduction.  With my tires that's 1.68 feet per second at 750 RPM.  With the 5.0 I'll be at 93:1 gear reduction and 1.35 feet per second.  Sounds great to me.  :)

06/01/04 - Ordered the Atlas
I ordered the Atlas from 4 West today.  It's due to arrive in 3 to 5 weeks. :(  I've got a trip planned to Dinkey Creek in about 3 weeks, so it looks like it's not going to get installed before then.

07/09/04 - Atlas II arrived
Well they pushed the 5 weeks to the very last day.  Actually, the case came in yesterday, but the shift kit was shipped seperate.  It arrived today  so I went and paid the bill and picked it up.  I'm delivering the 231 to the new owner tomorrow, so I went right to work getting it removed and cleaned up.  There was plenty of daylight left, so I went to work on the install.  Got most of the work done, but there's still some work left for Sunday and Monday.

07/11/04 - Further progress
I got some more work done on the install.  All that is left now is front driveshaft modifications.  I modified the rear shaft myself since all it needed was a little more length.

07/12/04 - Front drive shaft mods
I'm having the front shaft redone at the driveline shop mainly because it needs a CV joint where a standard u-joint currently is at.  In the past I've had a 2 piece front driveshaft with a carrier bearing.  A short piece, about 14" long went from the t-case to the carrier bearing mounted on the front of the skid plate.  The Atlas output is further forward and higher than the 231 output, so I don't have to have the carrier bearing anymore.  The shaft should be ready tomorrow or the next day.

07/15/04 - Complete, except for real world testing
I picked up my front drive shaft today.  No more carrier bearing.  When I tried to install it, the body interferred with the CV when it rotated.  I hammered up the body just a little to get the shaft installed.  On the first test drive down the street, the CV rubbed the body under hard acceleration.  I went back in the garage and made more clearance.  No more rubbing.  I went to a dirt lot to try out the front wheel drive with the cutting brakes and it seems pretty good.  There's a few guys going up to Big Bear this weekend and I plan to go.  That will be some better field testing.  I'm expecting the CV to still hit the body every once in a while, but we'll see.