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Rock Hard 4x4™ Supplemental Drill Bit Kit for JL Sport Cage Brace Systems [RH-90710]

Rock Hard 4x4™ Supplemental Drill Bit Kit for JL Sport Cage Brace Systems [RH-90710]

2 Reviews
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Part Number: RH-90710

RH4X4 Product Info

Please Note: This is a supplemental kit to what's already in most RH4x4 install kits.

2x 1/4" Cobalt Hardened Drill Bits
1x Conical Tree Die Grinder

The Why - Factory Design Complications
The Wrangler JL almost didn't come to market with solid axles. Weight was a major factor in determining if the Wrangler would sacrifice off road capability for fuel mileage standards. In the end, and what we have today, is a Wrangler attempting to both satisfy regulations and maintain its heritage. To save weight, and save solid axles, the JL engineers installed a very light weight, very thin wall (14 gauge), very body-integrated cage system.

To strengthen this lighter cage, the engineers produced an extremely hardened, odd shaped tubular design. In developing our Cage Brace System, we broke virtually every drill bit in our building. The tubing is unlike any material Jeep has ever used, certainly in the occupant safety realm. The shape requires a new way to install a Cage Brace System, and a back to the drawing board approach for us. After a fully year of research and development, we're proud to release our innovative design.

Drilling - Why 2 drill bits? Because odds are, you'll need 2. The new factory cage material, while only 14 gauge, is hardened. It takes a very slow (300 RPM ideal, 500 RPM max) drill process and a special hardened cobalt drill bit to penetrate. Your big box store drill bits will not work. The die grinder tree will help you remove burs and finish out the holes. You aren't required to purchase, but may very well need, an additional Drill Bit Pack.

RH4X4 Warranty Info

Product: No Warranty
Coating (if applicable): Due to varying climates and individual use, we cannot offer a warranty on powdercoating.


Average Customer Review:
( 2 )
TERRY NGUYEN from Aurora, CO United States
October 11, 2023
Drilling through the hardened steel was no joke, the extra bit came in handy. Worth the $$ for piece of mind too.
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Anonymous Person from Pasadena, MD United States
October 6, 2023
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