ok.. with my np231 issues, albiet minor right now, a short driveline causing a steep driveline angle, and gears not low enough to make me happy with my rig. As well as wanting to use 2Lo without having to turn my hubs in and out. I started thinking its time to go Atlas II 4.3.

Gear Tranny Tcase Axle Final Ratio
1 3.83 2.72 4.56 47.504256
2 2.33 2.72 4.56 28.899456
3 1.44 2.72 4.56 17.860608
4 1 2.72 4.56 12.4032
5 0.79 2.72 4.56 9.798528
R 4.76 2.72 4.56 59.039232

1 3.83 4.3 4.56 75.09864
2 2.33 4.3 4.56 45.68664
3 1.44 4.3 4.56 28.23552
4 1 4.3 4.56 19.608
5 0.79 4.3 4.56 15.49032
R 4.76 4.3 4.56 93.33408

Looking at my driving style closelye recently. I realized that I am in 2hi 60% on the trail, 2 lo (hubs turned out) 30%, and 4 lo 10% or so. I am either in 1st or 2nd gear lo or in 2 hi. I don't run 3rd-5th gear that often in 4lo.

Looking at my gears, I don't really loose anything, I'll just run 2nd and 3rd in place of 1st/2nd.

Anyone here drop a Atlas in to their post 90's YJ? (mines 4.0L/AX15/np231w/SYE right now) was it all bolt in? were any modifications necessary that needed grinder, welder, etc.?

I'm asking since I might try to get the Atlas real soon, but might only get it just in time to install it at Camp during Labor day weekend.

So.. convince me guys.. letting go of $2,500 or so is a tough thing to do.

Originally posted by twaldher
I don't really loose anything

except MONEY. IMO if you are in high range or 2wd lo 90% of the time on the trail, you have no need. if your gears werent deep enough then you wouldnt run high range at all.

why drop all that cash on something that you will not get any benefit from, aside from being able to say you have one?

you say how instead of running in 1st/2nd you will run in 2nd/3rd, well that seems kinda dumb. you are effectively keeping the same gear ratio then, so why not save the money and keep what you have?

replace the AX15 and transfer at the same time, both are pieces of junk heheh.

The AX15 is fine.

I would like lower for that 1-2% of the time that I get in to a situation where low gears would help me out. (Liken it to the guys that run 200+:1 ratios here, how often do you use them, but are they worth it when you need them? yes)

My 231 tcase has issues with only 1 year worth of wheeling on it. And its not even the chain with problems, its the output shaft and/or its bearings. I would just assume replace the 231 and not screw with it again. I still want to up the HP, go to 38s, and maybe switch to an auto someday. I don't think the 231 is up for that and be reliable at the same time.

When the AX15 craps out, a TF727 is probably going in.

I would like to have 2 Lo, without having to turn the hubs in and out. I need a turn radius, I don't have one now, but running in 2lo rear without turning out hte hubs, and having the option to switch to front 2lo to cut a corner would be nice.

Its always time to go Atlas:flipoff2: Do it anyhow that way if you sell your rig and don't really use the benifits of the Atlas some other lucky bastard can score

how many times do you have post and ask this ?

:flipoff2:


I would go with the 3:1 and a 727...or if you must keep your beloved ax15 still go 3:1 and just wait...once you get an atlas you will trash that tranny soon cause you will drive it like you got a atlas instead of a 231....

but then again the mall ain't real hard on stuff...

hehe

PS don't put it in at camp...sweet talk advanced and they should be able to send ya one quick

I put one in my '92 YJ behind a TF999. Took a little beating and cuttting a section of bracing from the tub, clocked it up as high as it would go and it fit. You'll have to cut some floor out to fit the shifters. I just welded some sheet metal over the old hole. I got mine from Steve N. - talk to him and see what he can make happen.

Originally posted by Moab Austin
how many times do you have post and ask this ?

:flipoff2:

PS don't put it in at camp...sweet talk advanced and they should be able to send ya one quick

Well, I started this in another thread cause I decided I should probably get one and get past the 231 problems for good. Was just hoping for some more encouragement to part with the $$$. :p

I just dropped in an Atlas 4.3 behind the AX15(4.56R&P) in my XJ and after running Fordyce on Saturday I am really pleased with the results. Before, I was in first gear most of the time and had to clutch it over tougher obsticles. Now I don't have to use the clutch and first gear is only used on the toughest sections of trail. 2-lo is nice too, although I didn't play with it that much since I'm just getting used to this new setup.
All in all the Atlas just feels right and the low gears make driving my junk a lot easier.
It also has that cool old-school style t-case gear whine on deceleration. :D


Jes

Originally posted by 9V


except MONEY. IMO if you are in high range or 2wd lo 90% of the time on the trail, you have no need. if your gears werent deep enough then you wouldnt run high range at all.

why drop all that cash on something that you will not get any benefit from, aside from being able to say you have one?

you say how instead of running in 1st/2nd you will run in 2nd/3rd, well that seems kinda dumb. you are effectively keeping the same gear ratio then, so why not save the money and keep what you have?

replace the AX15 and transfer at the same time, both are pieces of junk heheh.

I have to agree.....Doesn't sound like you need an atlas. The atlas is an awesome piece of machinery, but there are more cost effective alternatives.

Personally I think you should deep 6 the AX15 in favor of a real tranny...... SM420,SM465, NP435.All those trannys can be found for around $100 and would double your 1st gear low. Then for transfer cases, you can run a dana 20, dana 300, np205. Which can be had for $50 -$200, and all can be twin sticked. After selling your AX you should about break even. Then you'll probably need an adapter or two.

AX+Atlas 4.3
1 3.83 4.3 4.56 75.09864

My current setup
NP435+D20+4.56
6.69+2.46+4.56 =75.045744

SM420+D300+4.56
7.05+2.6(?)+4.56 = 83.5848