Rear suspension

Screwz

Greasemonkey
May 10, 2021
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GM used to sell stiffer 1LE rubber bushings. Rubbuer bushings don't really rotate, they twist which avoids binding. Poly bushings behave like metal bushings that don't allow deflection. However, G body rear suspensions require deflection to avoid binding.
I understand that the suspension needs some flex . And I know about the 1LE bushings that they haven’t made in years. I’m looking for an aftermarket bushing that would be similar to the 1LEs.
 

Rt Jam

G-Body Guru
Mar 30, 2020
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All valid points but I'm confident that most of the ride you are looking for comes from tire sidewall, shocks and springs.

Not here to debate that poly bushings will not add to the harshness but on a scale of 0-100. Poly is probably less than 5% of the comfort. Some of us are ready to give up that 5% in an exchange for accurate suspension travel. I also prefer the body and frame to be one, instead of it floating around on rubber bushing.
 
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gnvair

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Sep 1, 2018
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The current Moog replacement bushings have the identical "HARRIS" labeling on them as well as the same numbers as the NOS 1LE F body bushings I have in my possession.
I wouldn't think twice about using them.
 
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Rt Jam

G-Body Guru
Mar 30, 2020
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I don’t know why suspension companies don’t make a kit to get a modern ride there all about racing.

There is a simple answer to this. The options are limited due to the 4 arm suspension design.

Read back at my previous reply about articulation. In this scenario something has to conform to the articulation.
One choice is compliant rubber bushings. It can rotate in an arc for a few degrees but it also is soft enough to allow for twist. One minor drawback, rubber is loose, squishy and not accurate when loaded. The result when power is introduced, wheelhop.

Solution #2. A poly joint will stop wheel hop since it's stiff and accurate. Drawback, it can not articulate. If you force it to, it loads the mount. It can twist it off, oval out bolt holes or twist the arm. A real problem there if they are boxed.

Solution #3. UMI roto joints. Super accurate, allow for articulation but will transmit noise and harseness due to it's metal to metal qualities.

Solution #x There are probably more. Let's discuss.
 
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Clone TIE Pilot

Comic Book Super Hero
Aug 14, 2011
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There is a simple answer to this. The options are limited due to the 4 arm suspension design.

Read back at my previous reply about articulation. In this scenario something has to conform to the articulation.
One choice is compliant rubber bushings. It can rotate in an arc for a few degrees but it also is soft enough to allow for twist. One minor drawback, rubber is loose, squishy and not accurate when loaded. The result when power is introduced, wheelhop.

Solution #2. A poly joint will stop wheel hop since it's stiff and accurate. Drawback, it can not articulate. If you force it to, it loads the mount. It can twist it off, oval out bolt holes or twist the arm. A real problem there if they are boxed.

Solution #3. UMI roto joints. Super accurate, allow for articulation but will transmit noise and harseness due to it's metal to metal qualities.

Solution #x There are probably more. Let's discuss.

There is a 4th, poly roto joints. A metal sphere supported by poly races.
 
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scoti

Royal Smart Person
Sep 5, 2019
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Detroit Speed Swivel Links are an excellent option if not the best option for precision suspension control & ride quality. They offer superior non-binding articulation vs that offered by spherical/roto style joints (360° vs <45°) & utilize high durometer rubber (aka 1Le) bushings @ the ends for better isolation on the NVH harmonics. Yes, they cost more. They also offer more....

I'm swapping from Curries spherical set-up to Swivel Links. No miles on an actual set-up. But after I put hands on the Swivel Link to compare vs. the Currie arms in my possession (which are similar to the UMI Roto-Joint option), it was a no-brainer to me.
 
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69hurstolds

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Jan 2, 2006
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The current Moog replacement bushings have the identical "HARRIS" labeling on them as well as the same numbers as the NOS 1LE F body bushings I have in my possession.
I wouldn't think twice about using them.
I agree. The NON-1LE/B4C/FE2 Camaro/Firebird suspensions had "waffle" bushings, which seemed incomplete. They were more like rubber crosses shoved into the bushing outer sleeve leaving gaps around the bushing area. The Z28 4th gens used the same bushing as the 1LE. No big deal.

I can't say for sure, but I learned enough about them to suspect the "1LE bushings" weren't much more than full rubber bushings instead of the waffles. Could they be of higher durometer than say, the G-body full rubber ones? I dunno. Maybe. The interesting thing is that they're designed under that part number as applications only for the F-bodies. They will fit a G-body. I'm still not sure of any performance advantage over the G-body stock full rubber bushings, however. Maybe there is, maybe there isn't. Nobody's ever tested that, it appears. But these will flex.

After SLP was done doing the Camaro SS/Firebird Firehawk program in early 2000s, Dave Hamburger started selling off extra stock of SLP's (actually GM's 10164152) 1LE suspension bushings a few years after that, after the warranty periods ran out and SLP was no longer required to have warranty parts on hand. I bought a couple dozen off him then for a really decent price thinking I'd keep my 2002 SS forever. Sure enough, they're GM/Harris bushings, so it doesn't surpise me if Moog is still buying/packaging them.

"1LE" bushings have these markings...

HARRIS
B68
62538
FG


1682451295265.png


Here's a post I made about a year and a half ago about control arms the 1LE bushings:
---------------------------------------------------------------------------------------------------------------------

G-body LCA is 19.25" center to center. A-body LCA is 22" center to center. Not sure about the bushings.

But while we're on the bushings, there's always been this lore of 1LE bushings being the better LCA bushing. Even in the Camaro world. GM p/n 10164152. Heck, I even believed it 10 years ago. When SLP was getting rid of junk, I scooped up a couple dozen of the bushings for cheap, among other Camaro SS stuff.

An interesting thing happened on the way to the fair, however. While the 1LE bushing is indeed much firmer than the NON-1LE waffled bushings that came in the lesser performance versions of the Camaro, it is in fact, no different than a comparible full-solid Moog bushing. This was confirmed when the owner of a 4th gen Camaro changed out his LCA's for "1LE" LCAs. The 1LE bushings from GM had HARRIS, B68, 62538, FG molded into them. Interestingly, the Moog stock replacement bushing for the Camaro (K6178) had the same info molded into its bushings. They are essentially just a solid bushing vice the waffled ones. This is why they are perceived to be "better" than the stock bushings. But the better part is that they're not waffled.

If I had a Camaro parts book at the time I probably would have figured it out. I do now, though. The parts book says the 1LE bushing is the same p/n for FE2 (standard Z28), B4C (police) or 1LE application. Nothing special here.

Moog K6178 is the part number. Not sure what the newer ones look like nowadays, but it has been confirmed by the Camaro guys that it's the same bushing as the famous "1LE bushing". So if you see anyone pushing the Z28 bushings...

Another interesting item you see in the parts book from Olds is the "regular" upper LCA bushing is 10000068 (and lower for all) but the W40/W42 with 8.5 ring gear UCA bushing is 22526178. Another interesting point is that the K6178 is the standard replacement for EITHER of those. I couldn't tell you what, if any, difference there is for the 22526178 bushing vs. the 10000068. No idea.
 
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