Body lift pucks: Poly or aluminum?

KCsTJ

KCsTJ

TJ student
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Its time to install a 1" or 1.25" body lift on my 05 Sport.

Is there any difference or benefit to using:
  1. aluminum
  2. polyethylene
  3. or rubber puck spacers?

Right now I'm leaning towards a 1" aluminum body lift.
 
Aluminum pucks on top of the OEM mount. Aluminum doesn't deform when tightened to the proper torque like poly will.
 
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Poly 110%. Aluminum will transfer vibration. And if aluminum was the was to go, the factory mounts would have aluminum pucks.

Go with JKS, Savvy or Daystar.
 
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jjvw said:
Aluminum pucks on top of the OEM mount. Aluminum doesn't deform when tightened to the proper torque like poly will.
Click to expand...
To be fair, it depends on the "poly". There are some poly pucks that are acetyl or trade name Delrin which would work fine since it is a high mechanical strength engineering grade polymer. I would have no issue using it, but there is no cost savings over aluminum since it costs more than what the faster machining time saves.

I tried to use it for the Savvy body lift pucks but even with the post machining anodizing cost to turn them black, the aluminum is still cheaper than acetyl.
 
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For reference, this is what JKS does. I'm not getting the advertised 1.25" of added height.
77622

It didn't matter at the time, but that extra missing fraction helps with the tummy tuck. Additionally, the connection between the body and frame is not even because JKS can't be evenly torqued. This can lead to increased body ripples and deformation. Also, I want to raise the side body mounts. I won't do that until I can switch to the Savvy body lift so that I know where the new mount positions need to be, rather than rely on a squishy measurement.
 
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Thanks for the great feedback.

I'm looking at Mountain Off Road Enterprises 1" aluminum at the moment. $112.
I understand aluminum may transfer vibs, but my jeep rides so smooth now the vibs may not be an issue. (I hope)
I'll find out. ☺
 
TJ_2000 said:
Poly 110%. Aluminum will transfer vibration. And if aluminum was the was to go, the factory mounts would have aluminum pucks.

Go with JKS, Savvy or Daystar.
Click to expand...
I'm thinking perhaps there is some confusion going on. You have mixed up every aspect desirable and otherwise between your offerings and some are in direct violation of your logic of transferring vibes.

You need to understand the anatomy of a OEM body mount. The top rubber piece that sit on the frame mount is solid rubber. There is a mushroom cap with a hollow stem that drops down through it and that is capped off on the bottom with a steel washer that the bolt goes up through. The washer has a rubber cup bonded to it and the upper edge of the cup butts up against the frame mount. The weight of the tub sits on the solid rubber upper, the upward movement of the tub on bumps is controlled by the lower cup, and the compression of the assembly is determined by the tube that runs through the whole mess. All of the isolation is handled by the OEM mount so adding poly, aluminum, rubber or wood on top changes nothing about the amount of vibration transfer.

Due to the design of the mount needing a decent torque value to maintain its integrity and functionality, nothing should be put on top that can not achieve the same torque value on the fastener.

The JKS squishes when tightened, not good.
The Savvy works perfectly since it is aluminum.
The Daystar is a much harder poly than I prefer and it does have the tube inside to develop the torque, it is just a very hard poly and transfers more vibe than OEM.
 
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KCsTJ said:
Thanks for the great feedback.

I'm looking at Mountain Off Road Enterprises 1" aluminum at the moment. $112.
I understand aluminum may transfer vibs, but my jeep rides so smooth now the vibs may not be an issue. (I hope)
I'll find out. ☺
Click to expand...
No you don't understand.
 
mrblaine said:
I'm thinking perhaps there is some confusion going on. You have mixed up every aspect desirable and otherwise between your offerings and some are in direct violation of your logic of transferring vibes.

You need to understand the anatomy of a OEM body mount. The top rubber piece that sit on the frame mount is solid rubber. There is a mushroom cap with a hollow stem that drops down through it and that is capped off on the bottom with a steel washer that the bolt goes up through. The washer has a rubber cup bonded to it and the upper edge of the cup butts up against the frame mount. The weight of the tub sits on the solid rubber upper, the upward movement of the tub on bumps is controlled by the lower cup, and the compression of the assembly is determined by the tube that runs through the whole mess. All of the isolation is handled by the OEM mount so adding poly, aluminum, rubber or wood on top changes nothing about the amount of vibration transfer.

Due to the design of the mount needing a decent torque value to maintain its integrity and functionality, nothing should be put on top that can not achieve the same torque value on the fastener.

The JKS squishes when tightened, not good.
The Savvy works perfectly since it is aluminum.
The Daystar is a much harder poly than I prefer and it does have the tube inside to develop the torque, it is just a very hard poly and transfers more vibe than OEM.
Click to expand...


Your right. I for some reason thought savvy sold Polly mounts. I was always told and under the impression aluminum was a bad idea. I have the JKS and noticed it squished as well.

So you’re saying aluminum is the way to go?
 
JKS pucks deform when torqued by design. If you torqued the pucks correctly, you will obtain the full 1.25" advertised lift.

I love JKS products. Currie products are also great. Transferred vibes will be negligable. In most cases, the factory rubber mounts are reused and will help isolate vibes.
 
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ShredAZ said:
JKS pucks deform when torqued by design. If you torqued the pucks correctly, you will obtain the full 1.25" advertised lift.

I love JKS products. Currie products are also great. Transferred vibes will be negligable. In most cases, the factory rubber mounts are reused and will help isolate vibes.
Click to expand...

35ftlbs (torqued correctly) netted me less than 1.25in on JKS mounts and contributed to a damaged body on my red LJ. If you'd like them, I'll send you them for free but if they give less than 1.25in of BL you'll need to pay me for them.
 
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ShredAZ said:
JKS pucks deform when torqued by design. If you torqued the pucks correctly, you will obtain the full 1.25" advertised lift.

....
Click to expand...
Not in my experience. What I noticed is that as I worked my way around the mounts towards the final torque value, I would never reach it. The JKS poly mounts kept deforming because there is no hard limit to their compression.
 
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TJ_2000 said:
So you’re saying aluminum is the way to go?
Click to expand...
I didn't say that at all. I said you want something on top of the OEM mount that isn't compressible to achieve the proper torque value and does not squish. Aluminum, steel, brass, copper, beryllium copper, acetyl, ash, oak, maple, and a few other hardwoods would work. Each has various properties that make it more or less suitable, but all have the one we need which is enough mechanical strength to not squish.
 
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