My JK is stock (3.73 gear ratio, manual, 2.7 transfer case) except it now has 35 inch tire

I am planning to regain the lost torque (due to bigger tire) back. The only way
I know before is regear to 4.88 or 5.13

Then I saw an AD about Atlas II transfer case, which not only provides super low
10:1 ratio 4L. It also provide other modes like 4H, 2H, 2L. And it seems the 2L
can be used for front or rear wheel only.

So I wonder, if I install Atlas II, and put it in 2L mode while driving on street,
will it have the same effect as regearing?

But I wonder may be this is not good idea because transfer case is supposed to work for low speed driving? In normal situation, I put my stock transfe case in 2H while
driving on street, I guess this time the torque from engine goes
directly to axle so transfer case is not actually working?


If I put atlas II in 2L, the transfer case will defintely have its gear run. So
I wonder if I drive on the street, will it cause the transfer case overheat?

 

any low gear for the transfer case is ment for slow driving.. you would destroy your Tcase if you did that.

You will need to regear to compensate for the bigger tires.... Your power and torque is lost at the gears so the tcase will not change that for normal street driving.....

 

Thanks RyanBlack

So technically, if I engage 2L for rear axle I can regain the torque back, because
the 2L can choose ratio such as 2.0.

But in reality, it will burn the Atlas because 2L is only designed for low speed.

Am I right?

 

Yes you do not want drive on the street in 2low. In low it would triple your gear reduction in a 3:1 case. That would be like 11:1 gear ratio, so you would be at like 5500 rpm to go 40 mph.

Why would you spend $2500 on a Atlas when a regear may cost $1200.

 

I was planning to upgrade transfer case also. So I thought maybe using
the Atlas transfer case can avoid regear

Anyway, thanks for help. Seems like I have to do regear

 

Yeah, a regear is in my near future hopefully when the money is saved up for it..... I hear that the 513's are worth every penny....

 

I was forced to drive in 2L and can tell you you're not going to get any where quick. It's not the case that won't handle going quick, you just can't because of the gearing.