Rancho L1/EB1 Shock Eye Bushing

I run Rancho shocks on my 1985 Toyota 4Runner in a custom long travel setup. As such, I needed to use a 3/4" (19mm) dia. upper mount and had to open up the ID of the 5/8"/16mm Rancho bushings to fit. That took a lot of time with a burr and die grinder, hogging out the polyurethane. When those bushings started falling apart with age, I decided to try replacing them with 3D printer TPU parts. First, I could make them to the custom size needed. Second, I figured this would be a good place to test out the durability of a TPU bushing, since this is a somewhat non-critical part. If the bushings fail, the vehicle is still safe to drive, the shocks just make noise.

Details: https://www.4crawler.com/4x4/4R_suspension-III.shtml#LongTravelShocks

You'll want a soft filament as these bushings need to be pressed into the shock eye. Soak in hot water for 15 minutes before pressing them in. The standard "hourglass" bushing is 5/8" or 16mm ID, that's the unlabelled file or the one with "062" (0.625") in the name.

The other files are for 1/2" (050 or 0.50"), 9/16" (056 or 0.5625") and 3/4" (075 or 0.75") ID. I run a custom shock setup on my Toyota 4Runner and needed an L1 shock eye bushing with a 3/4" ID. I could use an L3 bushing, but it's too long. I sized these to print 1.4" long. I figured while I had the parametric file open, I would export versions in different IDs to fit different size mounting studs or bolts. If you need a longer or shorter bushing, scale the length in your slicer. I think the L3 bushings are about 1/4" longer. The L1 eye is 1-5/16", L3 is 1-9/16" with the bushing protruding from each side for clearance.

Not sure how long these bushings will last. The original urethane bushings lasted around 20 years. So this will be an ongoing test to see how a 3D printed TPU bushing will hold up. If you make some of these bushings, add a comment about the filament you used and the how they've worked for you.

You can purchase the original bushings from Rancho (RS978): https://www.gorancho.com/products/accessories-components/urethane-shock-bushings/rancho-replacement-urethane-shock-bushing-rs978.html

Print Settings

Printer Brand:

Type A Machines

Printer:

Rafts:

No

Supports:

Resolution:

0.4mm

Infill:

Filament: ZYLtech TPU Black

Notes:

Category: Automotive