Jeep Wrangler Forum

Jeep Wrangler Forum (http://www.wranglerforum.com/)
-   TJ General Discussion Forum (http://www.wranglerforum.com/f282/)
-   -   Should my rear axle roll while in park? (http://www.wranglerforum.com/f282/should-my-rear-axle-roll-while-in-park-239868.html)

OhSixTJ 05-02-2013 09:55 PM

Should my rear axle roll while in park?
 
In park, if "rock" the jeep, the rear axle twists a little causing the pinion angle to change. I know this happens on lead-spring equipped vehicles but should it also happen on my jeep?

I was underneath it, moving back and forth as I'm preparing to adjust the pinion angle tomorrow and wanted to see how movement affected the pinion angle.

Know what I mean?

PStov98TJ 05-02-2013 10:39 PM

How much movement are we talking here?

And some movement is inevitable. The axles movement isn't in a straight line but rather its an arc due to the control arms. Because these are fixed length once installed and rotate in a circular pattern, they also move the axle in a circular motion. Make sense?

OhSixTJ 05-02-2013 11:01 PM

Quote:

Originally Posted by PStov98TJ (Post 3713030)
How much movement are we talking here?

And some movement is inevitable. The axles movement isn't in a straight line but rather its an arc due to the control arms. Because these are fixed length once installed and rotate in a circular pattern, they also move the axle in a circular motion. Make sense?

I didn't measure but its a couple of degrees for sure. Seems like if I set it at exactly 0 degrees to the driveshaft, it would be above it by a couple of degrees during acceleration. Maybe it's bad bushings on the control arms?

PStov98TJ 05-02-2013 11:07 PM

I can't comment exactly on how much movement is normal as I've never actually seen an axle's movement under acceleration. But some movement of the pinion upward would be normal in theory (wheels go down in the front, axle rolls upward. remember that every action has and equal and opposite reaction, I'm a nerd I know, or maybe my physics professor is just good. Ha). However, how much movement is considered acceptable I can't say. I'll have to let someone else comment on that. But a few degrees seems like alot. Are you still on stock arms?

OhSixTJ 05-02-2013 11:10 PM

Quote:

Originally Posted by PStov98TJ (Post 3713139)
I can't comment exactly on how much movement is normal as I've never actually seen an axle's movement under acceleration. But some movement of the pinion upward would be normal in theory (wheels go down in the front, axle rolls upward. remember that every action has and equal and opposite reaction, I'm a nerd I know, or maybe my physics professor is just good. Ha). However, how much movement is considered acceptable I can't say. I'll have to let someone else comment on that. But a few degrees seems like alot. Are you still on stock arms?

No, rough country fixed lowers and I don't know what brand adjustable uppers. Both installed by the PO.

I know there will be *some* movement, but like you, don't know what's acceptable.

Patrick H 05-02-2013 11:13 PM

If you aren't familiar, you'll be surprised at how much it does move.

PStov98TJ 05-02-2013 11:14 PM

Well I can tell you this, RC control arms are known for poor quality joints that become lose and allow for movement. If I was you my first order of business would be replacing those with some higher quality CA's like currie with a JJ on the end. It's definitely worth the money. I'm planning on getting some in the next few year.

OhSixTJ 05-02-2013 11:15 PM

Quote:

Originally Posted by Patrick H (Post 3713179)
If you aren't familiar, you'll be surprised at how much it does move.

So then it's normal.

PStov98TJ 05-02-2013 11:15 PM

Quote:

Originally Posted by Patrick H (Post 3713179)
If you aren't familiar, you'll be surprised at how much it does move.

Good to know. I figured it'd move a bit due to the amount of torque seen by the axle. Just didn't want to definitely say yes or no. Thanks for the input!

OhSixTJ 05-02-2013 11:16 PM

Quote:

Originally Posted by PStov98TJ (Post 3713186)
Well I can tell you this, RC control arms are known for poor quality joints that become lose and allow for movement. If I was you my first order of business would be replacing those with some higher quality CA's like currie with a JJ on the end. It's definitely worth the money. I'm planning on getting some in the next few year.

Yeah that's my plan. I'm gonna try to save up to get adjustable for both top and bottom, front and rear.

PStov98TJ 05-02-2013 11:20 PM

Quote:

Originally Posted by OhSixTJ (Post 3713199)

Yeah that's my plan. I'm gonna try to save up to get adjustable for both top and bottom, front and rear.

Nice!! Good idea. Some defend RC. I've never personally owned any RC products but from the endless list of poor reviews, that's enough evidence for me. Good luck with your jeep!

OhSixTJ 05-02-2013 11:23 PM

Quote:

Originally Posted by PStov98TJ (Post 3713225)

Nice!! Good idea. Some defend RC. I've never personally owned any RC products but from the endless list of poor reviews, that's enough evidence for me. Good luck with your jeep!

Well it's been good to me so far. Hopefully it place nice until I can get those control arms haha thanks!


All times are GMT -5. The time now is 08:27 PM.