In both this thread and the spring thread, would it be useful to more clearly describe the primary purpose and function of a control arm joint/bushing (or a spring)? Are we over emphasizing an insignificant attribute at the expense of a primary one?
Does control arm bushing composition affect ride quality or NVH?
- Thread starter bobthetj03
- Start date
Oops, wrong thread. I deleted my post. Thought we were in the spring thread.
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Take pics of the bushings before you install arms so we can compare them to the synergy and Girro's
I'll try to do that. I think UPS brings half of them tomorrow. The other half is on back order. So it appears I'll have time to play with them in my living room.
I received my rear control arms yesterday. No pictures yet, but the lowers are very beafy. I didn't expect such a heavy arm. The uppers are a little smaller, but still plenty strong. Both appear to be well built. So my first surprise was how heavy they are. My second surprise was that the bushing was pressed in. On the website they show bushings with snap rings, so I was expecting a snap ring to hold it in, but they are pressed in on both ends.
As far as the D2 bushing itself, it looks indistinguishable from this picture of the Synergy DDB. Looking at it from the outside casing to the inside sleeve. I can see it has the steel casing where its pressed into the housing in the arm. It appears to be the same black 'rubber' outside durometer with the steel reinforcement ring and then the black harder inner durometer followed by the inside sleeve where the bolt goes through. All appear to be the same as in this picture.
EDIT: For comparison here is a picture from Rancho. This is how mine look.
NOTE: Looking at these two pictures the bolt sleeve in the DDB appears to have a slightly beveled corner that is not present on the Rancho D2. But this might be application specific.
Comments about the material: The 'rubber' of the different durometers is kind of interesting. I'm not sure what I was expecting, but I was surprised by the feel of the 'rubber'. Because the inner, softer, durometer is inset, you can't really get a feel for it, but the harder outside durometer, around the bolt sleeve, has a very smooth and clean hard rubber feel to it. I couldn't really describe it at first. Kind of like the sole of a hard shoe, but different. The more I felt it and played with it, it hit me. The material feels very similar to the the 'Crazy Balls' you can get out of kids vending machines at Walmart. Maybe a bit firmer. In fact, if I bounce the control arm on the corner of the bushing, it kind of has that same 'Crazy Ball' bounce to it. I'll admit that the idea of the control arms being cushioned by crazy balls creates a bad visual of a Jeep bouncing down the road, but I think any rubber material, including the stock Clevite, will have a certain amount of bounce to it. So I'm sure the material will function as its intended. No need to worry about bouncy off rocks like a Crazy Ball.
I did not have any experience of the inner sleeve sliding out as an earlier post about the Giiro joints suggested. Everything felt firm and tight. I could not even turn the inner sleeve by hand. So it takes some force to spin the sleeve inside the bushing. More like how the Synergy bushing was described. I might be able to get a better comparison here in the future as I am tentatively planning on using the Synergy JK bushings on the front axle side of the arm.
I will comment that it does take some force to flex the bushing. I stuck a screwdriver into the bolt hole to see how much I could flex it by hand. I got a little flex out of it, but it also bent the shaft on my screwdriver. Fortunately, the bolt hole is bigger than the screwdriver I used. If I can find a rod the same size as the bolt hole I will try another flex test.
All in all, I think the Rancho arms with the D2 bushings will be a solid product. I'll add more info here or create a new post with a review after I get things installed. But that might be awhile since I am still waiting for the front arms which are on back order.
As far as the D2 bushing itself, it looks indistinguishable from this picture of the Synergy DDB. Looking at it from the outside casing to the inside sleeve. I can see it has the steel casing where its pressed into the housing in the arm. It appears to be the same black 'rubber' outside durometer with the steel reinforcement ring and then the black harder inner durometer followed by the inside sleeve where the bolt goes through. All appear to be the same as in this picture.
EDIT: For comparison here is a picture from Rancho. This is how mine look.
NOTE: Looking at these two pictures the bolt sleeve in the DDB appears to have a slightly beveled corner that is not present on the Rancho D2. But this might be application specific.
Comments about the material: The 'rubber' of the different durometers is kind of interesting. I'm not sure what I was expecting, but I was surprised by the feel of the 'rubber'. Because the inner, softer, durometer is inset, you can't really get a feel for it, but the harder outside durometer, around the bolt sleeve, has a very smooth and clean hard rubber feel to it. I couldn't really describe it at first. Kind of like the sole of a hard shoe, but different. The more I felt it and played with it, it hit me. The material feels very similar to the the 'Crazy Balls' you can get out of kids vending machines at Walmart. Maybe a bit firmer. In fact, if I bounce the control arm on the corner of the bushing, it kind of has that same 'Crazy Ball' bounce to it. I'll admit that the idea of the control arms being cushioned by crazy balls creates a bad visual of a Jeep bouncing down the road, but I think any rubber material, including the stock Clevite, will have a certain amount of bounce to it. So I'm sure the material will function as its intended. No need to worry about bouncy off rocks like a Crazy Ball.
I did not have any experience of the inner sleeve sliding out as an earlier post about the Giiro joints suggested. Everything felt firm and tight. I could not even turn the inner sleeve by hand. So it takes some force to spin the sleeve inside the bushing. More like how the Synergy bushing was described. I might be able to get a better comparison here in the future as I am tentatively planning on using the Synergy JK bushings on the front axle side of the arm.
I will comment that it does take some force to flex the bushing. I stuck a screwdriver into the bolt hole to see how much I could flex it by hand. I got a little flex out of it, but it also bent the shaft on my screwdriver. Fortunately, the bolt hole is bigger than the screwdriver I used. If I can find a rod the same size as the bolt hole I will try another flex test.
All in all, I think the Rancho arms with the D2 bushings will be a solid product. I'll add more info here or create a new post with a review after I get things installed. But that might be awhile since I am still waiting for the front arms which are on back order.
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Without pics, it never happened!
Well, it kind of hasn't happened yet. They are just sitting in the box in my basement. Waiting for the fronts to come off back order.
Maybe over lunch I can grab a picture.
Here are a couple pictures of my Rancho arms and D2/DDB bushings. I put a quarter on the lower arm to give some scale to its heft. But I don't think the picture does justice to the size of the arm.
You can see the resemblance to the Synergy DDB in this picture. Note the bushing in the back arm has a small defect. I'm not sure if that little chip thats missing will be an issue or not. It looks like it is pretty well filled in with whatever expoxy they use to adhere all the different layers together.
I'm excited to get these installed. I wish the front were not on back order. I still need to order something on my front axle too.
You can see the resemblance to the Synergy DDB in this picture. Note the bushing in the back arm has a small defect. I'm not sure if that little chip thats missing will be an issue or not. It looks like it is pretty well filled in with whatever expoxy they use to adhere all the different layers together.
I'm excited to get these installed. I wish the front were not on back order. I still need to order something on my front axle too.
Can you remind us? Where does the rotation take place? At the inner sleeve or does the entire bushing move or does the bushing deflect?
My understanding is that the bushing will rotate around the steel bolt sleeve.
Check out this diagram of the Superlift Reflex bushing. I think its pretty much the same thing as the DDB, D2, and Giiro bushing. But their cutaway diagram is easier to understand. You can see the teflon liner is blue in the picture. So the inner steel sleeve would be bolted tight inside the control arm mount while the rest of the bushing rotates around that sleeve on the Teflon liner.
that is not a defect, it is just where they poured the rubber into the mold and cut the little part off.
oh I see the rear arm in the pic is missing a piece...I wouldn't worry about it.
oh I see the rear arm in the pic is missing a piece...I wouldn't worry about it.
I wonder how durable the Teflon layer will be once contaminants work there way in. I'm thinking heim joints, though I realize the movements between the layers is a little different.
OP
The DF doesn't use a Teflon liner and the bearing surfaces are also larger. That isn't a defense of Metalcloak, as they are in a similar ball park as far as stuff getting into the housing between the sliding surfaces. But the rubber seems to be a bit more forgiving than Teflon is.
The reason why the Jonny Joint isn't susceptible in the same way is because the preloaded race seals and wipes the ball, keeping the insides clean.
That is my biggest concern. But everything fits so tight, I don't know how anything could possibly get in there. At least when its new. My other concern is that I don't think teflon holds up well to hard impacts. So I don't know if a hard hit could crack the teflon or if it has some give. But then again, that layer of hard inner durometer rubber is pretty thin before you get to the steel reinforcement sleeve. So there can't be much room for any flex in there. That sleeve is also suppose to help with gaping. So you shouldn't get any dirt against the teflon layer. I don't know. It could all be a bunch of marketing BS. But because they have the bolt sleeve within another steel sleeve. It really seams like it should have a pretty tight seal that won't allow any dust to get in.
Honestly, the biggest reason that I have confidence in the DDB design is because Old Man Emu is using a DDB type of busing in their JK control arms and Mopar is using a DDB type bushing in their JL lift kit.
Unless I am misunderstanding something, it would seem to me the sleeve in the DDB is preloaded as well.
The JJ race is encapsulating the ball from all directions and then squeezed. At best, the DDB sleeve is shoved into a tight hole. The loadings are different because the shapes are different. As I understand it, a reason some of the JJ copies fail is because they reduced or eliminated the preload from the design.
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Thats not entirely true. Even the race for the JJ needs to have a hole where the bolt runs through the sleeve. I think dust could get in there just as easily as it does the DDB. But the advantage I see in the JJ is a little grease will push it back out.
Just looking at this picture. I see a pretty big hole in the side of each half of the race. It doesn't look that different to me as far as allowing dirt to get under the race.
