Novak Conversions Jeep Wrangler TJ engine mounts

Does control arm bushing composition affect ride quality or NVH?

Fair enough. And if you're happy with the results, that's all that matters. Just trying to stay within the spirit of the OP:

It's still a good exercise to think about these things and see what jeeples are considering as important, so I appreciate the participation.

But I think the question about cheap polyurethane bushings is reasonable. Are they any good? Or a waste of money?

"Good" meaning what exactly? Last longer? Isolate better? look cool?
 
I use to have a 1979 Pontiac T/A and when I decided to install a Polyurethane suspension and sub frame bushing kit the ride quality afterwards was pretty HARSH. After a few months I couldn’t take it anymore and switched back to a OEM rubber bushing kit and what a difference, the car was a pleasure to drive again.
I believe oem rubber bushings have a bit softer ride quality but that’s just my 2cents.
 
Polyurethane pretty much sucks anywhere on a suspension or engine/transmission mounts (edited) other than inside some control arm flex joint designs like Currie's Johnny Joints.
 
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It's still a good exercise to think about these things and see what jeeples are considering as important, so I appreciate the participation.

"Good" meaning what exactly? Last longer? Isolate better? look cool?
I guess we already know that PU lasts longer than rubber, although it does need maintenance to keep it from squeaking. But in this case, "good" means do they improve ride quality and/or reduce NVH?
 
Well ok, but don't those Currie and Metalcloak joints have PU in them?

JJ's have 2 hard races that surround the center ball. I don't know what material they are made from, but they are a hard, plastic like material. Duroflex bushings are rubber infused with Kevlar fibers.
 
Should we be thinking more about the importance of the body mounts as an isolater?

Funny how those mounts have not been mentioned, since they are the very last defense in dampening NVH to the butt dyno.

Did we ever learn what the intention is behind the recent addition of Kevlar?

Ain't "marketing" grand! Lol! I'll let you know in another 32K miles, k.
 
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Here is the reason I wanted to explore track bars. If one believes that the control arm joints and bushings have a meaningful effect on the telegraphing of NVH into the body, then it makes sense to put an isolative connection on both ends of the control arm. Why then would that same someone put heim joints in the track bars, the 5th link in the factory suspension? If the answer is a bushing, then the front frame side is understandable. A bushing can't work there. It is what it is. But if the factory used two bushings on the rear track bar, then why not copy that with two improved bushings? Why add a heim where there wasn't one before. And why not use the signature bushing?

If Metalcloak wants us believe that the Duroflex bushing can reduce NVH, why did they put heim joints in their track bars? Why do they not use the Duroflex bushings in their own track bars? Why the inconsistency from one suspension link to another if the intention is to reduce NVH?
 
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Should we be thinking more about the importance of the body mounts as an isolater?
I'll bite. It's great having fresh body mounts! I replace my old cracked body mounts and clocked the difference with my butt dyno right away!
 
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Here is the reason I wanted to explore track bars. If one believes that the control arm joints and bushings have a meaningful effect on the telegraphing of NVH into the body, then it makes sense to put an isolative connection on both ends of the control arm. Why then would that same someone put heim joints in the track bars, the 5th link in the factory suspension? If the answer is a bushing, then the front frame side is understandable. A bushing can't work there. It is what it is. But if the factory used two bushings on the rear track bar, then why not copy that with two improved bushings? Why add a heim where there wasn't one before. And why not use the signature bushing?

If Metalcloak wants us believe that the Duroflex bushing can reduce NVH, why did they put heim joints in their track bars? Why do they not use the Duroflex bushings in their own track bars? Why the inconsistency from one suspension link to another if the intention is to reduce NVH?

The TB doesn't see the same loads a control arm does. Why do you think just about every TB made has a rubber bushing at the axle end? It doesn't matter what is at the frame end as long as it provides the horizontal movement needed for a TB on a TJ. JJ, tie rod end, heim joint, as long as you have a rubber bushing at one end to dampen, it doesn't matter. I'm still trying to figure out the rear.
 
I just asked elsewhere about the use of a bushing on the front axle side. It's purpose for Currie and for everyone else's front track bar is to keep the bent bar from rolling and creating it's own clearance issues. It's an occasion where a self centering bushing serves a purpose. That still doesn't answer the question of why MC can't use a DF in that particular location. Especially if it is true that the track bar doesn't see the same loads as a control arm. Why is it ok in one link but not the other?
 
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Yes Currie's Johnny Joints do, I was only really thinking of the other locations. Poorly/incompletely worded on my part.
Actually, I agree with you. The cheap polyurethane bushings are crap. But a well-designed joint/bushing performs well, regardless of what it's made of.
 
It's purpose for Currie and for everyone else's front track bar is to keep the bent bar from rolling and creating it's own clearance issues. It's an occasion where a self centering bushing serves a purpose.
Huh. So why is it ok to put two JJs on the rear track bar? Aren't there clearance issues back there too?
 
Huh. So why is it ok to put two JJs on the rear track bar? Aren't there clearance issues back there too?
It's a less bent bar. And they add a set of rubber washers to the outside of the JJs to limit the roll.
 
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Yep there's no difference. I replaced a 5.5" RockKrawler short arm suspension with an RE 4.5" long arm into my previous TJ, no noticeable ride difference. Then after that Jeep was stolen I bought my present TJ with a Currie 4" short arm suspension. No difference there either. I can see a stupid high suspension lift with extremely steep short control arm angles riding really stiff but that's it.

I am new to this but wouldn't 5.5" lift short arm to a 4.5" short arm require a spring change at a minimum? And possibly a shock change? If you changed shocks and/or springs it is not a very good comparison. I met a guy with a long arm on the trail that claimed that changing from short arms was the best mod he has made. He used the same shocks and springs and claimed street manners were much improved. He also had control arms with solid heim joints and claimed harshness was no issue.
 
Novak Conversions Jeep Wrangler TJ engine mounts