I answered that in the other post you have about leveling kits. Other than the two self inflicted issues, no other problems. I love the leveling kit.

 

Hey Keats, are your Dak front axles Rapezza joints or Cardans? I know Rapezzas can be a b*tch when you do any type of a suspension lift, but Cardans don't really have a problem with increased angles.

Grand Cherokee 4x4s used to come with either and the most in demand upgrade for guys who have Rapezzas who lift their WJs are Cardan front drive shafts...

 

good question. I was going to assume cardans...here is a pic of the inboard joint:



and the cup it goes into:


I "assumed" the outboard joint was the same. Could be wrong.

 

There's your problem - that's a Rapezza joint - looks like a CV with a boot. They want to run at just the angle they are setup at, too much angle as in lift and they fail. You can probably get away with 2" of level with no severe flex off-road and be ok. Same problem you get with too much level on an IFS 4x4 without using drop brackets to keep the CV axles at stock angles.

A Cardan joint has no boot and basically looks like two U-joints back-to-back. They can take any angle you throw at 'em. My Grand Cherokee has the Cardan because it's got the Overland package - thank goodness because I've got 3" oversize coils on it...

Here's a pic from an XJ (regular cherokee) with 6" of lift, you'll see how the angle gets "straightened out" going into the differential by the second joint:

 

That's the exact same type of thing I had to get for my ranger when I got a 4 inch. They called it a Dual-Cardan specifically. Without the second joint, it was said that the life span of the shaft was reduced to less than 30k miles.

 

I'm currently debating on what to do to avoid the CV and rack & pinion accelerated "destruction" after a leveling kit installation and haven't yet made up my mind on what I'll do. I was looking at the front axles some time ago with thoughts towards changing the joint style, but I don't believe there's enough room to use double cardan joints, plus, there's additional fabrication that would need to be done to connect this type of axle. From my quick look, you'd need a double cardan at each end of each axle shaft to accomodate different angle (angle coming out of the diff isn't the same as the angle going into the hub).

 

i'm going to chance it. I dont offroad. axles are @$60 so I'm not too worried about it.

 

Yes, specifically it's a double Cardan joint, Jeepers commonly just refer to them as a Cardan since you either have one or a Rapezza. I've never even seen an axle with only a single Cardan joint.

I'm told that one of the popular Jeep axle shops will build a double Cardan for ANY application. Tom Woods Custom Drive Shafts is the place. I have no personal experience since my Jeep already has a double Cardan...

 

A solid tubed front axle is a good candidate for single cardan joints since the geometry around the joint doesn't change except for the steering (suspension has no influence on the angles) - my YJ uses single cardan joints on the front axle. This still isn't the ideal solution because of the properties of a single cardan joint but since this is a factory design, I'm stuck with it. To change it, I'd need to make room and mounting for a different joint - for a double cardan for example, I'd need to cut back the axle tubes and fabricate a new knuckle assembly (the double cardan requires a lot more room than the Rapezza or the single cardan).

You can get custom made double cardan shafts made for any application if you want to throw money at it AND wish to waive the builder's liability. Shops like "Tom Woods" typically make double cardan drive shafts for any application because they aren't safety related, but when you start to tinker with safety related design, you won't find many fabricators that will belly up to that liability - this includes the single cardan joints in steering shafts (like the intermediate shafts).

Here are a couple of double cardan drive shafts I made by modifying a jeep XJ front drive shaft - these 2 shafts are for my current YJ, the short one is the rear drive shaft.

DriveShafts-01.jpg