Well I smacked up my rear drive shaft pretty good. It's got a few nice dings in it and I get some serious vibration at higher speeds. So, obviously the next step is to get it replaced and I might as well upgrade it at the same time. I spoke with a local drive line place and they said the whole thing needs to be replaced and he started listing of a bunch of parts that I need (not just the shaft). He then proceeded to tell me that I would also need the get adjustable upper control arms. Does this sound right? It's a 4-door Rubi with a 3" zone lift on 35's. Forgive my lack of mechanical knowledge but can someone shed some light on this?

 

Aftermaket cardan shafts generally like different angles than the joints on the stock cv shafts. Hence the recommendation for adj ca's to tilt your axle.

The extra parts are probably for swapping the yokes (stock shafts) at the axle and t-case to new flanges (cardan shaft). Or maybe I have that backwards?

If cost is an issue, you might just browse your local craigslist for a take-off from someone that went aftermarket.

And if you have some time to burn, go out to Tom Woods website and click the JK link for some info, including a link to an install vid (which didn't work for me?). Then click the tech info link at the top for even more.

 

Well that seems to make sense. Thanks for the reply. So I need to swap out the UCA's but I can still keep the stock LCA's?

 

Upper and lower do the same thing, just backwards from each other. Which set you replace is up to you.

Rear upper - lengthen to raise the pinion / shorten to lower the pinion
Rear lower - shorten to raise the pinion / lengthen to lower the pinion

Having both uppers and lowers let's you move the entire axle forward/backward in the wheel well, as well as fine tune the pinion angle in the rear, and both caster and pinion up front.

Which is better if you only get one set? Shortening the lowers will shorten the wheelbase (bring the axles closer together) by a very, very small amount. Some arms may not go short enough to get the angles where you want them. (probably more important up front for caster than in back for pinion angle?). But, having beefier aftermarket ca's on the bottom instead of the stock arms can be a good thing, depending on your usage.

 

http://stomperoffroad.com/catalogsea...drive+shaft+jk

This is where I got my front drive shaft, very happy with it. I'm sure you'll like the price of the rear shafts too