Guntar13

I am thinking the better route to go for my 3 inch lift is the SYE, might as well knock out any problems before they happen. I am reading about the shims for the axle and wonder to what degree you should go for a 3 inch lift? is there a chart someone has a link to that explains all of that a bit better. BTW for cost savings as much as possible i want to use the front driveshaft from an auto for the rear driveshaft, i can find them very plentiful in the JY around here. Any recomendation on a SYE that utilizes that type of drive shaft. looked at a few and some of them say they do and some don't say at all. thanks for your help

1999 4.0 AW4

DaBeebs84

Get an angle finder and measure.....or go to a drive line shop and have them do it. Every vehicle is different....some may need 2*, some may need 6*

xjheep92

I don't want to be a broken record but iro hnt yoke works with a front shaft not sure what other ones do.

Also im running 3degree shims. I put them in at 3" I'm now at 4.5" and they are fine.
You want the rear pinion yoke pointing straight up at the Tcase or just slightly below

ta2tony

The Iron Rock Offroad Hack'n'tap works with the front DS swap...or any similar SYE.

As far as the shim angle, there is no way to tell until you get your jeep lifted. Honestly, if I were you I wouldn't even worry about an SYE until you lift your jeep. You may not need one.

MountiansRcool

i would go with the hack and tap because

1. its cheaper
2. if ur tcase explodes u can just take off the sye and put it on a new one

Guntar13

So you can't use a front drive shaft with a non hack and tap SYE?

Just wondering cause I'll be real honest I'm not cutting the output shaft, don't want any part of that!

ta2tony

Depends. Look at the picture of the IRO HNT (the one for about $100). The picture shows a yoke that mounts to the output shaft of the TC. Any kit you buy that has a yoke like this included will work with the front DS.

Some SYE kits come with a flat flange (round w/ 4 holes). Those will not work with a front DS unless you also purchase the yoke adapter that mounts to it. Just make sure you get an SYE kit with a yoke...

AndyB

I just went through this. My 2001 has 6 degree shims on it with a 3.5 inch Rubicon Express lift (but I actually got more like 5 inches out of it). You can check Tom Wood's website for some good information.
Use the angle finder to determine the difference between your driveshaft angle and the pinion (differential) angle. The ideal angle is 1 degree below the driveshaft. Shims are installed under the leaf packs. The shim will change both the driveshaft angle and the pinion angle, but not equally. I started with 12 degrees of difference. 4 degree shims got me to 6 degrees difference. 6 degree shims have me within 3 degrees.
The shims should be installed under the centering pin (bolt) that holds the leaf together.
The steel shims that RE sells have a 5/16 hole in them, needs to be opened up to 3/8. I bought new bolts. You could probably use 3/8 inch cap screws from the hardware store.
Put it on jack stands, remove the wheels. Disconnect the rear shocks, then remove the ubolts. Put c-clamps on either side of the leaf to hold them together, then remove the centering pin. Install the shim and longer centering pin, tighten, remove the c-clamps, reinstall everything. Only takes about 30 minutes.
You can measure the pinion angle across the yoke with the driveshaft removed, or you can measure across the machined surface on the back (Tom Wood). You can also put identical 8 mm sockets on the u-joint strap bolts and measure across those.
I installed my SYE with the case still in the Jeep, if I was doing it again I would do it that way. Easy to do, don't have to remove the case, no problems so far.
Good luck with your project.

Guntar13

That is definately more of the type of info I was looking for thank you!

Happysjeep

I am about to do hack and tap Friday, any helpful notes I need to know and what front ds do I need to go look for?

Barrelmaker

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