Advise needed on new drive lines

[Rentalman]

Hi all. I'm getting ready to upgrade my drive lines and I'm looking for some knowledgeable advise. My Scout II has a 4" Sky Jacker Lift with 5" shackles and the front axle has a cut and turn. Currently I'm using the original drive lines. They are attached to Dana 44's front and rear and a Dana 20 T-case that has 10 spline yokes. I have zero drive line noise or vibration from the OEM drive lines. They work great. I'm sure I need to get longer drives shafts due to the 4" lift. I do not have an angle finder so I used an angle finder app that I downloaded. The rear drive line is at a 16 degree angle and the front is at 19 degrees. Do I need to order a rear drive line with a double cardan joint? From the videos I watched they mention if you are over 15 degrees you should use a double cardan joint and you will need to point your rear pinion toward your t-case. Forums I've read said not to use shims to acheive this. So if I need to go this route do I need to have the rear axle perches relocated to point the rear pinion toward the t-case. If I can get away with just longer drive lines I would prefer to go that route. As always I appreciate all of the input. Pictures included of my rear drive line for viewing of the angle.

 

[Winchested]

Your stuff is fine, equal and opposite angles.

You don't need double cardan shafts on a 4" lift. And you only need a different front if you did a reverse shackle install.

 

[Rentalman]

Winchested, thank you for the reply. So my OEM drive shafts will be fine with the 4" lift and I do not need to order any longer ones? That is great news. Also I do not have a reverse shackle set up on the front axle.

 

[Winchested]

Winchested, thank you for the reply. So my OEM drive shafts will be fine with the 4" lift and I do not need to order any longer ones? That is great news. Also I do not have a reverse shackle set up on the front axle.

Yes, sometimes the front driveshaft may bind at full droop but that is usually if your axle has never had a cut and turn and you use the angled shims to have better caster, you then sacrifice pinion angle. The cure was running an offset Tom woods u joint. However that u joint is only good at slow speeds.

I think you rig is set up well now that you've had the cut and turn done.

On the driveshafts, with the stock style shackle set up, you don't need much more than 1-2" of slip in your driveshafts. When you reverse shackle the front... You need 4-6+ inches of travel. If wheeling it hard.