Rubicon with NVG241OR transfer case, driveline issues

[Gone&DoneIt]

I was under my rig today (new tierod) and noticed the rediculous angle my driveshaft is at. Everyone has been telling me I need to install an SYE kit to help with the vibration and ease some of the stress on the u-joints,... Many arguments have incurred over this,... Am I completely nuts, doesn't the Rubicon already have a fixed yoke from the factory????? I am 99.9% sure on this,... but everyone tells me I am wrong.

If it is a fixed yoke,... what can I do to reduce the angles on the driveshaft? I've already blown out one coupler in Moab,... I can only imagine this is going to be a regular occurance as hard as I wheel it. I apprecite the advice all.

Jack

 

[Utah_jeepster]

All rubicons came with factory SYE's.
As to how to change the angle, you will need to get adjustable upper control arms, these will allow you to change your pinion angle. I know that Tera-flex and R.E. make a set...hit up Quadratec. I know they have a set in the magazine.

 

[Bounty__Hunter]

How much lift do you have?

The important thing to consider is proper ujoint angles. In the stock Rubi rear driveshaft configuration of two single cardan ujoints, the ujoint angles must be identical (meaning the D44 pinion and the transfer case rear output will be parallel).

If your lift is high enough, you will benefit from a double-cardan rear driveshaft (commonly referred to as a CV driveshaft, same design as your front driveshaft). A CV rear driveshaft will allow you to point your rear D44 pinion directly at the transfer case rear output, where the pinion will be parallel with the rear driveshaft. This alleviates poor driveline angles in high lift applications.

Like mentioned above, adjustible upper control arms are needed to adjust the rear pinion angle. There are many manufacturers making bolt-in CV driveshafts that will bolt to the rear of a Rubi transfer case.

 

[currupt4130]

Tom Woods and Jesse at High Angle both make CV shafts for the rubi. There are two options, you can replace the balancer that the stock driveshaft bolts to with a yoke, or use an adapter to that balancer. Tom Woods talked me through the whole thing when I ordered one for my dad.

 

[Gone&DoneIt]

If your lift is high enough, you will benefit from a double-cardan rear driveshaft (commonly referred to as a CV driveshaft, same design as your front driveshaft). A CV rear driveshaft will allow you to point your rear D44 pinion directly at the transfer case rear output, where the pinion will be parallel with the rear driveshaft. This alleviates poor driveline angles in high lift applications.

Like mentioned above, adjustible upper control arms are needed to adjust the rear pinion angle. There are many manufacturers making bolt-in CV driveshafts that will bolt to the rear of a Rubi transfer case.

6"'s of lift, Teraflex L.A. kit. I have a Tom Woods double cardan cv axle.

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I think the issue is the adjustable uppers. I bought the adjustable upper control arms, but they are not long arms, just the flex arms. the uppers in both the front and rear are short (fronts are actually stock). Should I switch to upper control arms to match the long arm lowers? What benefits will I get (besides the pinion angle mentioned above)? I noticed the sway bar pins (not the pins you put them on when released, but the ones you attach them to when it is locked in) are bent on the passenger side. Apparently under full passenger side flex the tie rod end that attaches to the drag link is hitting the swaybar mount and has signifigantly bent it. My buddy at Scorpion thinks this is due to the short uppers,... I guess I am not sure just how much I am screwing up by running the stock uppers in the front and the short flex uppers in the rear. Help Fella's!

 

[currupt4130]

The problem with Tera Flex's Long arm kit and just buying the lowers, is that it screws your geometry to hell when you flex. By this I mean your pinion moves like its praying to Allah when your axle droops and stuffs. I'll try and illustrate what I'm talking about.

Look at the upper arc in this picture, that is your upper stock short arm.
Now look at the lower, thats your long arm. By the time your axle has traveled down the vertical lines on the right side of each arc, the arcs have traveled extreme different distances. If you travel all the way down the arc on the right of your short arm, the arm is pointing straight up and down. Now travel that distance down the line on the right of your long arm arc, see where the arms will be in comparison to each other? The arms attatched to the axle on the left. This is causing your pinion to rotate.

 

[TwistedCU]

I would heed Bounty's advice. Your friends are half right. They're wong about the SYE (Rubi's fixed output) but correct about the stress on the U joints. A CV driveshaft is far more forgiving to the liftyed short wheelbased Jeep.

Driveshaft, adjust the arms you have. That's what I would do to correct the problem you have.

I would then take a long hard look at Teraflex's "long arm kit" and the way your axle gets tweaked when the long lower arms droop while the short upper arms fight to keep up. I don't know if Teraflex has long (hopefully adjustable) upper arms available as an upgrade but if they do it might be the most cost effective way to go.

I've read posts from guys on NAXJA who run the same kit on their XJ's (virtually identical setup) and seem to praise them but the geometry doesn't make sense and there seems to be as much negative feedback as there is positive. From the looks of things you like to wheel that Jeep the way it ought to be wheeled. I'd complete your long arm conversion if that's the case.

 

[Bounty__Hunter]

I'd go with long upper control arms, or change the lowers to radius arms with Y-links to attach to the UCA mounts at the axle.

 

[Gone&DoneIt]

thanks all, I contacted Teraflex and got the part numbers yesterday to go to a full four link setup. I am waiting on prices from the local shop.

 

[Gone&DoneIt]

this is nuts. $1640 for the upper long arms, truss system and brake lines!!!! There has to be another kit. I was thinking I could fab the truss brackets for about $50 in flat stee, the arms for 4 Heims and some 2" tubing and you can buy brake lines for @$80. $1600?!?!?!?!?

Anyone have 3 and 4 link suggestions that aren't so absurd???

it is insane.....

Thanks,

Jack

 

[Gone&DoneIt]

I am looking into the Full Traction 3 link front and 4 link rear kit. I think it will work with the Teraflex Long Arm kit I have now. Keep your fingers crossed.

 

[Gone&DoneIt]

guess I am ordering the rest of the teraflex kit tomorrow. Grrrrrr. Just dont feel like what i am buying is anywhere near worth $1600.00.