Atlas II

[Mudderoy]

I was watching a new episode of Xtreme with Ian Johnson yesterday, and they are rebuilding a 2001 Jeep TJ for a double amputee soldier. John Curtain, I believe is his name. Good thing is John is helping Ian rebuild it!

Ian decided that along with changing out the 2.5L and standard transmission that came in John's TJ they install a freshly rebuilt 4.0l, don't recall the automatic, but instead of going back with the original transfer case Ian is installing a Atlas II!

John asked a real good question when Ian said the Atlas has two shifters... WHY?

The response was it allows you to run 2wd low and when needed 4wd low. Great for making tight turns on the trail, especially when you don't need 4wd.

Other than being able to do this, swap from a driver's side diff axle to pass side axle what else does this $2500 transfer case do for you?

https://www.samsoffroadllc.com/orders/image/cache/data/transfer%20case/Atlas-II-2-500x500.jpg

[prerunner1982]

Other than the available low ranges that it could have... it's shiny.

Low Range: 1.5:1 or 2.0:1 or 3.0:1 or 3.8:1 or 4.3:1 or 5.0:1

And if it's being built for you... why not.

[abebehrmann]

They're also gear driven and a whole lot stronger than a stock T-Case. Ask Steve, 4.3LXJ, I'm pretty sure he has one in his Jeep.

[4.3LXJ]

Ask Steve, 4.3LXJ, I'm pretty sure he has one in his Jeep.

Actually I have the 4 speed. But in essence, the 4 speed is the Atlas II with a planetary on the front.

But to answer the question, there are several advantages. The first is strength. The gears inside are huge and I will go out on a short limb and say that there is not a stronger tcase on the market from anyone short of what is in a 6X6 that you can get and still fit it in a Jeep. Second is the twin stick design. Originally, the Atlas design, which was a beefed up Dana 300, had a single stick for the convenience of the general public. But you can get a twin stick conversion that allows you to run each axle independently on the 300. Normally, the average guy would just shift in the front axle like we would with an NP231. But with our chain driven tcases which are good for milage, you can have a little trouble getting it out of 4WD. With the Atlas, you just push on the lever for either axle and let off the gas and it shifts out. Normally the Atlas comes with detent pins in it so you cannot run 2WD in high range (liability issues for them). I took them out of mine along with the synchro rings and it shifts much better and allows me to use any range on any axle. Each lever operates the range on an axle. You can do a front burn, something I have yet to need but the professional rock crawlers us it all the time. Also, the Atlas is easy to shift in and out.

[4.3LXJ]

Ask Steve, 4.3LXJ, I'm pretty sure he has one in his Jeep.

Actually I have the 4 speed. But in essence, the 4 speed is the Atlas II with a planetary on the front.

But to answer the question, there are several advantages. The first is strength. The gears inside are huge and I will go out on a short limb and say that there is not a stronger tcase on the market from anyone short of what is in a 6X6 that you can get and still fit it in a Jeep. Second is the twin stick design. Originally, the Atlas design, which was a beefed up Dana 300, had a single stick for the convenience of the general public. But you can get a twin stick conversion that allows you to run each axle independently on the 300. Normally, the average guy would just shift in the front axle like we would with an NP231. But with our chain driven tcases which are good for milage, you can have a little trouble getting it out of 4WD. With the Atlas, you just push on the lever for either axle and let off the gas and it shifts out. Normally the Atlas comes with detent pins in it so you cannot run 2WD in high range (liability issues for them). I took them out of mine along with the synchro rings and it shifts much better and allows me to use any range on any axle. Each lever operates the range on an axle. You can do a front burn, something I have yet to need but the professional rock crawlers us it all the time. Also, the Atlas is easy to shift in and out.

Also, the case itself is thick aluminum. Josh bounced his 242 case on a rock and lost it. With the Atlas T6 aluminum, the rock might be worse for the wear.

[Mudderoy]

Steve, looking at one install it looks to be a huge pain in the ass. How was yours?

When you say 4 speed, that's a term that makes me think of a transmission which yours isn't, right. Just a transfer case?

[4.3LXJ]

Yes, it is just a transfer case. But it has 4 speeds if you count 1:1, just like a transmission. But it runs both axles in those speeds. And yes, it is not just a direct bolt in. The hardest is making the shift levers clean inside the cab. On the Wrangler though, they have kits that make it easier

[Mudderoy]

Yes, it is just a transfer case. But it has 4 speeds if you count 1:1, just like a transmission. But it runs both axles in those speeds. And yes, it is not just a direct bolt in. The hardest is making the shift levers clean inside the cab. On the Wrangler though, they have kits that make it easier

Can you use the Atlas as a substitution for changing the ring and pinion in the diffs? I suspect you'd have to have a pretty tall tire for this to be practical though.

[prerunner1982]

You could run a more highway friendly gear ration in the axles and still have a low enough 4wd option for off road. If I remember correctly though the axle gears may not survive long taking all that torque though.

[4.3LXJ]

If you are thinking about highway use, then no. It is not practical. The easiest way to do that is to not use overdrive.

[bluedragon436]

Got a friend (the one I bought the LA, OTK steering and double shear TB from), who is selling his Atlas II TC.. If only I had like $2k to spare... lol

[LizardRunner]

I have plans to get the 4 speed, wife has said that once I get the farm buildings up and the house built, I can make the additions to the Red Lizard that I've wanted. So in maybe 4 more years I will have my atlas tc at last.

[denverd1]

Actually I have the 4 speed. But in essence, the 4 speed is the Atlas II with a planetary on the front.

But to answer the question, there are several advantages. The first is strength. The gears inside are huge and I will go out on a short limb and say that there is not a stronger tcase on the market from anyone short of what is in a 6X6 that you can get and still fit it in a Jeep. Second is the twin stick design. Originally, the Atlas design, which was a beefed up Dana 300, had a single stick for the convenience of the general public. But you can get a twin stick conversion that allows you to run each axle independently on the 300. Normally, the average guy would just shift in the front axle like we would with an NP231. But with our chain driven tcases which are good for milage, you can have a little trouble getting it out of 4WD. With the Atlas, you just push on the lever for either axle and let off the gas and it shifts out. Normally the Atlas comes with detent pins in it so you cannot run 2WD in high range (liability issues for them). I took them out of mine along with the synchro rings and it shifts much better and allows me to use any range on any axle. Each lever operates the range on an axle. You can do a front burn, something I have yet to need but the professional rock crawlers us it all the time. Also, the Atlas is easy to shift in and out.
Way stronger than a NP205? Got a friend putting the gear driven 205 in his YJ. Just curious how much stronger an Atlas would be. Money IS a concern so I'm not trying to change his mind, just curious about the two compared

sent from my Samsoon S5 from the bottom of a mud hole

[4.3LXJ]

The Atlas is massive inside. I don't have a comparison, but one area that will be stronger is the mounting on the front. I would put the case up to the 205 anytime. Very thick 256 T6 aluminum, which has similar tensile strength to mild steel.