T-minus 8 hours until the Atlas 4-speed install begins

Not as strait forward as I had hoped. It is bolted in. Had to do quite a bit of clearancing at the rear to get it up high enough. And where AA tells you to mount the 4 speed shifter does not work because it hits the tcase before it is up high enough. I guess if I had a 2” body lift I would have no issues but who would want that crap. So tomorrow I will figure out where to now mount the hi low shifter. And then modify the skid plat just a touch. Then I can measure for driveshafts. I think the front will be ok. But the rear is going to have to be shortened about 2.5” - 3”. I’ll know for sure tomorrow.
Will you be able to reuse your 4wd switch which turns on the 4wd light in the dash?
 
Got the belly skid modified and back very slightly in place. The new case hangs out the back behind the end of the belly skid and the sight tube is too vulnerable for my liking so I’m going to extend the belly skid by about 6” to the rear with a 45 degree bend up after the first 3” - 3.5”. We still have an issue mounting the high low shifter so I think I may cut a hole in the driver or passenger side tunnel and build a level box into to mount the third shifter vertical. Got the shaft measurements. Front shaft measurement is 3/4” longer than original and rear shaft needs to be 2 3/4” shorter than what it was. It will 42 1/4” long up front and be 16” long in the rear at ride height. Thank goodness I had the rear stretch as that is getting short. I’m hoping that my current Tom Woods shafts can be modded to work. Dropping them off in the morning. It’s been a lot more work but will be worth it in the end.
 
Will you be able to reuse your 4wd switch which turns on the 4wd light in the dash?
I could have but I bought a new switch for like $15 from ADvance adapters when I ordered the case. I did have to lengthen the wiring harnesses for the 4wd switch and the speedometer sensor but it wasn’t to big a deal just added a little time. Should have it buttoned up and driving by Tuesday when I get the driveshafts back. I only worked on it about an hour today.
 
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Awesome, can't wait to hear how you like it. I know one person on JF that has one and if I remember correctly he mounted the high-low shifter on the passenger side.
 
Well the millennial anti theft device install is almost complete. So many levers to play with.

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I plan on dong a complete write up with pictures when I get some time but for today I got both driveshafts back in and got the high low shifter installed in its final location. Had to build a plate to cover the original hole and location the Advance Adapters tells you to locate it so I made it oversized and installed nutserts in the floor pan Incase I need access to adjust the cable shifter. It will be easier and I wouldn’t have to use self tapping screws etc. Tomorrow I will put the boots on and get the center console and driver seat installed and go for a test drive. Then I will begin work on mounting the new PRP Enduro Elite seats.
 
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I was under the impression that the Atlas was shorter than the OEM tcase. Is this incorrect?
 
You'll really enjoy it. I absolutely dig my 5:1 A II.
What kind of setup are you running? What type of terrain do you normally wheel? I'm torn between the 5:1 Atlas 2 vs a couple combos of the Atlas 4. No purchase will occur for some time, but I can at least plan.
 
It's a 2003 TJ, 4.0, NV3550, Atlas 5:1, 4.88's, 60/44, Warn hubs, chromoly axles and ARB's. And now on 37's. In the rocks mostly to make use of the crawler gears. If I need to catch up to my buddies, I just shift into O/D for a short bit at 12 mph. Or shift on the fly out of front drive into neutral and rear drive into high until low range is needed again.
With the manual, just let the clutch out and idle through. There's no need to bump up things and if I need to stop, I push the clutch in or turn the key off.
I'm not really into sand dunes but, creek or desert washes is done in high range.
 
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What kind of setup are you running? What type of terrain do you normally wheel? I'm torn between the 5:1 Atlas 2 vs a couple combos of the Atlas 4. No purchase will occur for some time, but I can at least plan.
The Atlas 2 speed is shorter than the 231. The 4 speed is about 2.75” longer if you choose to retain the speedometer output. I chose the Atls 4 speed with the 1:1, 2.72:1, 3.8:1, 10.34:1 ratios. I removed a 4:1 case. I run all sorts of trails all over Colorado, Utah and New Mexico mostly. I chose to go with the 4 speed as a lot of times the 4:1 was too low but the 1:1 was not low enough. Plus the added benefit of 2 wheel drive low and front dig capibility. I will now be able to run 2.72:1 like most of the others out there then still have my 3.8:1 close to my 4:1 and I doubt I’ll use it but maybe it will be awesome the 10.34:1 is there if needed.
 
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I’m running a 99 Tj with 4.0L, Ax-15, rockjock 60 rear, Core 44 front, ARB’s, 5.13’s, 37’s, PSC hydro assist, 4 linked 5” stretch in the rear soon to be 4” stretched 3 link up front.
 
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Well i won't need a speedometer output as I'm GPS now, but 2.72 is way too fast and my gear ratios are numerically low. In all honesty I don't know how low is low enough. But I know 2.72 with 3.07s and the 3.83 in first is WAY too fast. My truck has a crawl ratio of around 70 and I like that a lot, but I don't know what to compare for anything numerically higher than that. I simply don't have a reference.

Also I've done 0 inches of trail with substantial rocks. I don't really want to rock crawl, but if there's an odd rock on a trail I need to go through and there's someone that can guide me through, I'm not against crawling.

I'm planning to go to 3.55s when I go ARB and get stronger shafts (30 spline rear 1541, but 27 spline in the front chromoly I think). I'm running 33s and open at the moment Dana 30/35.

With 3.55s, 5:1 and 3.83, I'll basically be crawling about what a Rubicon would offer. But I really don't know if I'll want to go slower and I like the idea of having the other higher ranges, but I've got 5 gears at my disposal and then 1st Hi cuts off very similar to where the 5th low is. Much of this is just the question of how much does a grand mean to me, but I hate to get something I don't need.

Also I've moved a few objects in 2wd where using 2wd lo might be very handy to get a load up and moving and then switching to 2 hi. Until my turbo kicks in there's not a crazy amount of torque, though I've heard there may be some EGR stuff occurring, but I really don't know for sure.
 
Well after getting to drive it yesterday I’m stoked. This thing is going to be a beast. I love the ability to choose my low range and the 2wd low ranges. I had to play with the front dig a bit just because. And I think the 10.34 low low range will be used more than I anticipated. It may just get me in trouble though
 
I've always been interested in an Atlas upgrade. I ran into a couple install videos last week and there were some complaints about the gear noise at highway speeds. A lot of gear noise at highway speeds would be a deal breaker for me.
 
Thats good news. I really want to install the Atlas for the additional strength and gear ratios. I'd be interested in hearing from others.
 
Mine is a whole lot quieter than my 231 with Terralow kit was and pretty sure it’s quieter than my stock case was as well.