I've been researching lift's and the drive shaft problems associated with the high angle but it seems like I'm coming across a lot of conflicting info so I thought I'd just come out and ask and hope for a clear response!!

Unfortunately I don't have the budget to do what I want on a Rubicon so I'm looking at an 08 2DR 6 speed that will give me the 3.73 gearing instead of the 3.21 on 07 and 09. My main concern is the drive shaft and the future problems I will have with the lift height. I was considering the Rusty's 3.25 on 35's. I'm located in the Midwest so the most this lift will help with is going through the snow and light trail use. But, this will be my daily driver as well. Would it be smart to buy an aftermarket drive shaft (Tom Woods) and can I get away with just the rear or do I need the front as well?

My second question is about gearing. Will running 35's with 3.73 gears allow me to use 6th or will I be stuck at 5th? I'm not a speed demon so losing 6th isn't a major concern.....but, I do travel on the interstate quite a bit so I'm looking to hit 70mph at the most.

Any info would be greatly appreciated! Thanks!

 

ON THE ISSUE OF DRIVESHAFTS: My research has came to conclude:

Anything more then 3"+ in suspension lift - Automatics will have to worry about their front drive shafts. Manuals don't seem to have this problem.

Rear drive shaft problems will occur to 3"+ height on TWO DOOR both automatic and manual transmissions Jeeps. The pinion angles which are super steep without the rear upper control arms, will pre-maturely wear down your rear drive shaft's components.

Four door jeeps, don't seem to have the same problem that TWO DOORS have with their rear drive shafts...

 

Here is some info on gearing. I found it useful.

 

Now with all this being said; just to make sure everything is clear replacing the front and rear DS with aftermarket DS will correct all of these issues?

 

No. As far as I know, when you lift your Jeep, you alter the geometry at which your drive shafts will be angled at; therefore, you will need upper control arms to set pinion angles to save the rear drive shaft, aftermarket or not, it will wear prematurely unless you get suspension components to compensate or adjust for your needed geometry.

I'm sure others that have been around the forum longer then I have can come in to answer better on these specifics.

 

Dang pluke you sound like a mechanic now.

I'm running 3" FT lift 6speed manual,and have had 0 problems with the ds thus far.

Goodluck onyour quest for parts sir

 

I have done alot of research on this topic before putting my lift on. What I learned is that you will need to replace both drive shafts. A friend of mine blew one of his out before he changed.

Second, I would not not not order the lift from Rusty's simply for the reason that you are gonna get killed in shipping. Seriously, like over $100 dollars killed. For my rig I ordered the Tereflex 2.5 spring kit (which actually gave me 3" of lift) from David at Northridge and also ordered the JKS adjustable front trackl bar at the same time for less than what the Rusty's kit was going to be with shipping. Shipping was free with David.

You will loose your 6th gear with 3.73's and 35" tires. I would suggest 4.88s.

 

You are correct. When you lift your jeep you change the angle of the shaft compared to the angle of the rear diff. You want them to be as close to a straight line as possible. Thats the reason for the UCAs. They return the caster to an acceptable angle.

From what I have seen happen, the problem with the shafts is that they don't use a traditional universal joint so the factory shafts are not as forgiving as the universal joint shafts.

 

Thank you all for your input, I really do appreciate it. What is the max lift height people are running on 4 doors without running into DS problems? 2.5 inch, 3 inch?

 

The answer to this is going to be ALL over the board.

Check out the link below, this is where I spend 95% of my day (These should answer some of your questions):

https://www.jk-forum.com/forums/show...272#post211272

Specifically,

Q: What are all the components that I will need with a 3" lift?
A: At bare minimum, you should have a set of 3" coils, bump stop extensions, longer shocks, rear brake line extension brackets, new longer rear sway bar links (factory links can be installed up front), adjustable front track bar and rear track bar relocation bracket. Optimally, I would recommend adjustable front upper and lower control arms as well as they will help you set your caster to the appropriate angle it needs to be. Also, if you have a 2-door, adjustable rear upper control arms and a new double cardin U-joint style drive shaft would be highly advisable.

Most importantly. You'll have to ask yourself some questions.

Money
Tire Size
Daily Driver
Off-road Usage