The Synergy Dual Durometer Bushing (DDB) Series is engineered to deliver smooth, bind-free suspension movement with zero maintenance. Featuring a grease-less, self-centering design with up to 30 degrees of misalignment, these bushings combine a soft outer durometer to absorb vibration and allow flex with a hard inner durometer that serves as the bearing surface for a free-floating inner sleeve. An internal bushing ring prevents sleeve gapping during extreme articulation, ensuring consistent performance and long service life. Designed as a direct replacement for aftermarket control arms using OEM clevite-style bushings, DDBs are compatible with all Synergy suspension components and can even be used in custom fabrication applications!
Looking for a complete forged rod end so you don't have to press bushings out and back in? Check out our Forged Rod Ends with Dual Durometer Bushings to make your refresh quick and easy!
Fitments:
Please verify the part number of the part you are refreshing and review the notes below prior to ordering. If you have any questions, reach our to our support team at support@synergymfg.com for additional assistance.
| Part # | Description | Fitment | Mounting Width (A) |
Bolt Size (D) | OD (C) |
Housing Part # |
|---|---|---|---|---|---|---|
| 4320-01 | LOWER CONTROL ARM BUSHING |
8033, 8036, 8046, 8047, 8051, 8052, 8153, 8551-04, 8154, 8231, 8551-01, 8563-01, 8585, 8232 |
2.618" | 9/16" / 14MM | 2.249" | 4408-01 |
| 4320-02 | CONTROL ARM BUSHING | 8551-02, 8563-02, 8583-02, 8583-04, 8851-01, 8870-01, 8871-01, 8891-05, 8892-06 | 2.618" | 5/8" / 16MM |
2.249" | 4408-01 |
| 4320-03 | DODGE LOWER CONTROL ARM BUSHING | 8551-03, 8563-03, 8583-03 | 2.618" | 3/4" / 18MM |
2.249" | 4408-01 |
| 4320-04 | BRONCO REAR CONTROL ARM BUSHING | 7052-01, 7054-01 | 74MM | 5/8" / 16MM |
2.249" |
4408-01 |
| 4320-05 | BRONCO REAR CONTROL ARM BUSHING | 7052-01, 7054-01 | 70MM | 5/8" / 16MM |
2.249" |
4408-01 |
| 4321-01 | JEEP FRONT UPPER CONTROL ARM BUSHING | 8053, 8853-01 | 2.000" | 1/2" / 12MM |
2.124" | 4410-01 |
| 4321-02 | JEEP UPPER CONTROL ARM BUSHING | 8151, 8152 | 2.000" | 3/8" / 10MM |
2.124" | 4410-01 |
| 4321-03 | FRONT UPPER CONTROL ARM BUSHING | 8035, 8891-07, 8853-01 | 2.000" | 1/2" 12MM |
2.124" | 4410-01 |
| 4322-01** | UPPER CONTROL ARM BUSHING | 8038, 8054, 8854-01, 8553-01, 8892-08 | 2.360" | 9/16" / 14MM | 2.124" | 4407-01 |
| 4322-02 | UPPER CONTROL ARM BUSHING | 8038 | 2.618" | 9/16" / 14MM | 2.124" | 4407-01 |
| 4323-01 | JEEP TRACK BAR BUSHING | 8062, 8068, 8075, 8087, 8233-03 | 1.600" | 9/16" / 14MM | 1.499" | 4402-01 |
| 4323-02 | JEEP TRACK BAR BUSHING | 8155-01, 8156 | 1.600" | 1/2" / 12MM |
1.499 | 4402-01 |
| 4324-01* | DODGE TRACK BAR BUSHING | 8550-01, 8550-02 | 1.600" | 9/16" / 14MM | 1.624" | 4409-01 |
| 4324-02* | DODGE TRACK BAR BUSHING | 8550-01, | 1.600" | 5/8" / 16MM | 1.624" | 4409-01 |
| 4324-03 | 21+ BRONCO REAR TRACK BAR BUSHING | 7062-01 | 2.188" |
5/8" / 16MM | 1.633" | 4803-01 |
| 4326-02 | FRONT UPPER CONTROL ARM BUSHING (AXLE SIDE - 2007+ JK, JL, JT) |
8012-15, 8012-16, 8012-18 | 2.000" | 1/2" / 12MM |
1.782" | 8012-18 * |
| 4327-01 | JEEP TRACK BAR BUSHING | 8075-02, 8862-01, 8875-01 | 1.600" | 9/16" / 14MM | 1.758" | 4409-01 |
| 4327-02 | FORD TRACK BAR BUSHING | 8675-01, 7675-01, 7675-02 | 1.732" | 13/16" 20MM |
1.758" | 8675-01* |
| 4327-03 | DODGE RAM 2500/3500 2003-2008 | 8550-11 | 1.600 | 9/16" / 14MM | 1.758" | 4409-01 |
| 4327-04 | DODGE RAM 2500/3500 2008.5-2013 | 8550-11 | 1.600 | 5/8" / 16MM | 1.758" | 4409-01 |
| 4328-02 | DODGE RAM 2500/3500 2014+ |
8704-01 | 1.63" | 3/4" / 18MM |
1.875 | 4810-02 |
| 4328-02 | DODGE RAM 2500/3500 2014+ |
8704-11 | 1.63" | 3/4" / 18MM |
1.875 | 4810-11 |
Specifications:
| Part # | A (MOUNTING WIDTH) |
B (SHELL LENGTH) |
C (OD) |
D (SLEEVE ID) |
|---|---|---|---|---|
| 4320-01 | 2.618 | 2 | 2.267 | 0.563 |
| 4320-02 | 2.618 | 2 | 2.267 | 0.638 |
| 4320-03 | 2.618 | 2 | 2.267 | 0.717 |
| 4321-01 | 2 | 1.75 | 2.135 | 0.505 |
| 4321-02 | 2 | 1.75 | 2.135 | 0.402 |
| 4321-03 | 2 | 1.5 | 2.135 | 0.505 |
| 4322-01 | 2.32 | 1.75 | 2.135 | 0.563 |
| 4323-01 | 1.6 | 1.25 | 1.508 | 0.563 |
| 4323-02 | 1.6 | 1.25 | 1.508 | 0.525 |
| 4324-01 | 1.6 | 1.25 | 1.657 | 0.563 |
| 4324-02 | 1.6 | 1.25 | 1.657 | 0.638 |
| 4327-02 | 1.732 | 1.375 | 1.758 | 20mm |
| 4328-02 | 1.6 | 1.41 | 1.887 | 0.717 |
Features:
- Synergy Dual Durometer Bushing (DDB) Series
- Feature a maintenance free, grease less design.
- Self centering with 30 degrees of misalignment. (4320-01, 4320-02, 4320-03)
- Outer "soft" durometer acts as bushing cushion and flex material.
- Inner "hard" durometer lining acts as the bearing surface to allow free floating inner sleeve to rotate. Provides for a maintenance free "zero bind" bushing.
- Internal bushing ring separates inner and outer materials to prevent inner sleeve gaping at extreme flex.
- Direct replacement available for aftermarket control arms using OEM Cleveite style lower control arm bushings.
- Bushings available for all suspension components made by Synergy MFG as well as many other companies.
- Bushings are sold complete with inner sleeve installed.
- Check out the Video!
IMPORTANT: Dual Durometer Bushings (DDB) are not a replacement for Synergy products that originally came with Johnny Joints. These bushings are only replacements for Synergy products that came with Dual Durometer Bushings (DDB). Please call/email for more information on specific products. 805.242.0397 / support@synergymfg.com
- Parts in red do not yet come with these bushings.
- 4320-01, 4320-02 and 4320-03 have nylon outer shell
- 8550-01 track bars built 5/19/2015 and newer and 8550-02 track bars built 2/13/2015 and newer require replacement bushings 4324-01 or 4324-02 depending on bolt size
- If your track bar is older than the specified dates above, replacement parts are no longer supported
- 4327-03 & 4327-04 are an updated stiffer bushing for the 8550-11
- If your control arms or track bar have bushing halves or heims, replacement parts are no longer supported
- Upgraded versions with our Dual Durometer Bushings are available!
- *Housing only available as part of 8012-18 kit