Rear lower control arm ?'s
#11
JK Super Freak
Like this:
Last edited by ShutterBug; 04-20-2016 at 09:16 AM.
#12
JK Junkie
I'll never get this driveshaft thing understood.
#14
JK Junkie
The top one looks like you have a much more flexible joint at the trans so you angle the pinion to let that joint take the misalignment. The bottom one looks like both joints are the same so you split the angle between the two. With two rzeppas the bottom one makes sense to me. But if I understand correctly it's the top one?
Last edited by 14Sport; 04-20-2016 at 05:24 PM.
#15
JK Super Freak
It's the same reason RCV axle shafts don't bind the same way that a standard U-Joint axle will.
#16
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I would agree with Shutterbug. I did some reading about angles and some shop experience. The Rzeppa is a CV joint, just like those found on FWD cars. There are limits to the angle but much more than the standard u-joint. The Rzeppa is mainly limited by the boot shape. Ideally both joints should point directly toward each other.
Even if you get the pinion angle ideal with the driveshaft, the angle will be off at the transfer case; again limited by the boot shape of the Rzeppa joint. Then could go on to debate that the springs will bow due to the tilt of the spring perches.
I think in my case, it won't be an issue. I haven't had a chance to get it out much. Its not my DD and doing a few other things. With the length of the unlimited, and my minimal lift, it won't be a concern.
Even if you get the pinion angle ideal with the driveshaft, the angle will be off at the transfer case; again limited by the boot shape of the Rzeppa joint. Then could go on to debate that the springs will bow due to the tilt of the spring perches.
I think in my case, it won't be an issue. I haven't had a chance to get it out much. Its not my DD and doing a few other things. With the length of the unlimited, and my minimal lift, it won't be a concern.
#17
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#18
JK Junkie
Thanks, guys. The science just doesn't make sense to me. The double cardan by its very nature splits the DS angle in half among its two joints. Problem solved. The rzeppa doesn't. So why force the entire angle on one joint? And if you do, why install a second rzeppa rather than a much cheaper, perfectly good, tried and true option of a single cardan? Why have two rzeppas. Double cardan drive shafts don't have 2 double cardans. And the factory is dealing with a smaller angle than a lifted Jeep.
The questions are rhetorical. Not looking for any answers. These are just the things that make me go hmmmm.
Appreciate the help but I'll stick with sparky stuff.
The questions are rhetorical. Not looking for any answers. These are just the things that make me go hmmmm.
Appreciate the help but I'll stick with sparky stuff.
Last edited by 14Sport; 04-21-2016 at 07:03 AM.
#19
Thanks, guys. The science just doesn't make sense to me. The double cardan by its very nature splits the DS angle in half among its two joints. Problem solved. The rzeppa doesn't. So why force the entire angle on one joint? And if you do, why install a second rzeppa rather than a much cheaper, perfectly good, tried and true option of a single cardan? Why have two rzeppas. Double cardan drive shafts don't have 2 double cardans. And the factory is dealing with a smaller angle than a lifted Jeep. The questions are rhetorical. Not looking for any answers. These are just the things that make me go hmmmm. Appreciate the help but I'll stick with sparky stuff.
Actually here, this is a stock joint rebuilt with TF's kit
#20
Not to mention with a double cardan if you're off an ass hair on your pinion angle they vibrate