OP
MC is local for me, so saved on shipping. Oh, and I drank the Kool Aid and gots drunk.
Does control arm bushing composition affect ride quality or NVH?
- Thread starter bobthetj03
- Start date
MC is local for me, so saved on shipping. Oh, and I drank the Kool Aid and gots drunk.
OP
I would need to replicate the factory arm mount bracket and clamp said replication to a vise.
I love the honesty...
The fact that you had JJ, then went to MC and now you are saying you didn't notice a difference is actually quite valuable information. Most guys after dropping a few hundred dollars will say that whatever they put on is better than what they had before. There is some kind of psychological need for us to justify the money we have already spend. So looking solely at your response we have a couple options: 1) Other changes you made to your system offset gains in NVH made by the arms 2) your but dyno is not calibrated properly 3) Currie coolaide is what is being given out at the time and your just drinkin whatever they are given
My guess is either 1 or 2. It does seem like some guys are much more sensitive about changes made to the Jeep than others. I have a friend who is extremely aware of how his jeep rides. He would noticed a difference in how his JK would ride and handle by simply changing the control arm geometry on his AEV drop brackets by one hole. Its a very subtle change that most people would not notice. I don't think I could tell the difference when I drove it in the different settings, but he could. So I keep wondering if the difference in NVH is just that small and subtle.
Now I need to look back at your post and see what all you had before and what all you changed...
FWiW, I know someone locally who built an axle for his TJ with MC arms. One of the axle side brackets was not in line with the frame side which put the DF into a permanent state of misalignment. The bushing eventually delaminated from the inner ball. While the less than perfect fab work is not MC's fault, a different style joint would not have failed.
If you pay too much attention to me, you might notice how little I talk about certain aspects of my suspension.
With the remaining clevite, there is still the issue of accommodating the amount of increased rotation.
OP
I really don't want to make this thread about Duroflex joints, but since it's what I've got to work with, I'll post some further observations.
I don't see a whole lot of wear around the circumference of the bushings where they rotate in the barrel. The grease was all gone and there was evidence of some chaffing of the rubber along the inside of the barrel.
top bushing new, bottom 32K miles.
The only real noticeable wear is on the end of the bushing where the retaining washer has worn deformed the rubber a bit.
I don't see a whole lot of wear around the circumference of the bushings where they rotate in the barrel. The grease was all gone and there was evidence of some chaffing of the rubber along the inside of the barrel.
top bushing new, bottom 32K miles.
The only real noticeable wear is on the end of the bushing where the retaining washer has worn deformed the rubber a bit.
That is a big assumption. Permanent misalignment with any joint is going to eventually fail.
With a heim joint. With a Johnny Joint? Explain how and why? This is the exact same reason a bushing cannot be used in the frame side of the front track bar.
OP
The cliff notes version: OME 2.5" lift on 31's, everything else stock. A few years later, developed DW, bad. Balanced tires 3 times and rotated. Didn't help. Found some play in the front TB ball joint. Replaced it with a new JKS TB. Didn't fix it. Upgraded steering with ZJ upgrade. Better, but still got the onset of DW. Replaced the front lower control arms with Curries. Fixed it. During all of those shenanigans, the only noticeable thing I felt was when I upgraded the tie rods, and that didn't completely solve the DW until I changed the lower arms. That is when I felt the most significant change. Not only did it cure my DW, the steering response and feel was more pronounced. Can we perceive this change as more or less NVH?
Claiming one joint would not have faild because of theory is one thing. Putting that joint in the same situation is another.
Track bars return to alignment, when set up properly. The control arm wont.
OP
Does a JJ or a heim lose integrity or strength if it's not returned to center at rest? How about when it's under load? Under load for prolonged periods?
Here are a few of the heim joints and Johnny Joints on my Jeep, including a Metalcloak front track bar. None of these joints have a return to alignment, nor do they care what misalignment they were last left in. A bushing will respond very differently.
Neither a JJ or a heim care about being returned to center or to any position. But like any joint or bushing, if there is a constant uneven loading, such as when a single control arm is adjusted too long or too short, the life span will be reduced.
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NEWS UPDATE:
That heim joint on the rear Synergy trackbar was bothering me. So I called Synergy. The tech I spoke with told me they now use the DDB on both ends of their rear track bar. He said that was an old picture. He did not know why they used the heim joint previously. He stated that their joints have no problem being in misalignment. So that might change perspective on the durability of the DDB, but it still doesn't answer any questions about NVH.
I asked the tech about NVH but he was vague and said he had never been in a Jeep with Clevite or JJ so he couldn't make any direct comparisions. He could only say he rode in a Jeep for 4 hours with the DDB and it rode really nice... Duh, I sure hope it would.
So no news on the NVH front. But I think the fact that they use their DDB in place of Clevite everywhere tells us a little more about their target audience and the role that the DDB performs.
That heim joint on the rear Synergy trackbar was bothering me. So I called Synergy. The tech I spoke with told me they now use the DDB on both ends of their rear track bar. He said that was an old picture. He did not know why they used the heim joint previously. He stated that their joints have no problem being in misalignment. So that might change perspective on the durability of the DDB, but it still doesn't answer any questions about NVH.
I asked the tech about NVH but he was vague and said he had never been in a Jeep with Clevite or JJ so he couldn't make any direct comparisions. He could only say he rode in a Jeep for 4 hours with the DDB and it rode really nice... Duh, I sure hope it would.
So no news on the NVH front. But I think the fact that they use their DDB in place of Clevite everywhere tells us a little more about their target audience and the role that the DDB performs.
OP
I hear the word "Synergy" and all I can think about is JK/JL crowd. Really surprised that they are making TJ stuff quite honestly. Their DDB is interesting for sure. Wonder if they will go the extra mile and make a retro kit for the TJ front uppers?
Dang I forgot to ask about that. I think I need front uppers too. Check out this page on their website:
https://www.synergymfg.com/synergy-dual-durometer-bushing-ddb-series.html?category_id=4970
They show front uppers but its not clear which Jeep they are for. Are these the correct dimensions for the TJ front uppers. For some reason, I thought they actually had the TJ DDBs released before the JK stuff.
OP
Their website is vague as to the fitment, but I'm not sure how those would be able to press in to the factory upper mounts. If the outer housings are the same dimensions as the Clevite bushing outer sleeve, then I guess it could be possible.
Isn't that how it would have to be? How else would you do it? How are other axle bushing replacements done?
OP
Correct, no other way unless you weld in one of their housings somehow. Good luck on the cast driver side mount.