Ridetech 11227298 Rear Upper R-Joint Bushing Kit 1964-1977 GM A-Body 1978-1988 G-Body Pair

The Ridetech 11227298 is a rear upper trailing arm R-Joint bushing assembly built specifically for 1964-1977 GM A-Body and 1978-1988 GM G-Body vehicles, including the GTO, Chevelle, El Camino, Cutlass, Monte Carlo, Regal, and Grand Prix. This R-Joint kit replaces the factory rubber bushing with a precision-engineered assembly featuring a 17-4 investment cast stainless steel housing, polished stainless ball, and RTX10 composite self-lubricating cage. The result is a dramatically improved rear suspension pivot point that eliminates bind, reduces deflection, and restores accurate wheel geometry under hard cornering and braking. Sold as a pair with four R-Joint spacers. Made in the USA in Jasper, Indiana.

Why the Ridetech 11227298 R-Joint Outperforms Factory Rubber

Factory rear upper trailing arm bushings are made from rubber bonded to a steel shell. They work fine at stock ride heights under stock spring rates, but the moment you lower the car, stiffen the springs, or start pushing the chassis hard, rubber bushings introduce compliance that defeats the purpose of every other suspension upgrade you have made. The bushing deflects under load, the axle housing shifts, and the geometry changes in ways the engineers never intended for performance driving.

This R-Joint eliminates that compliance with a true ball-and-socket joint pressed directly into the axle housing bore. The 17-4 stainless steel housing provides the rigidity the factory rubber never could. The polished stainless ball rotates freely in all axes, so the suspension moves exactly where the geometry tells it to move, not where the rubber lets it twist. The RTX10 composite cage is self-lubricating, so there is no grease fitting to maintain and no degradation from moisture or road contamination.

• 17-4 investment cast stainless steel housing: corrosion resistant, dimensionally stable
• Polished stainless ball: multi-axis articulation with zero compliance
• RTX10 composite self-lubricating cage: maintenance free, no grease fittings required
• Press-in design: installs into the factory axle housing bore, no custom fabrication
• Pair included: both sides covered with one part number

What's Included with 11227298

• 2x Ridetech R-Joint bushing assemblies (one pair, driver and passenger side)
• 4x R-Joint spacers

Important: The bushing removal and installation tool (Ridetech Part 85000011, sold separately) is NOT included with RID11227298. This press tool is required to properly remove the old bushings and install the new R-Joints without damaging the axle housing bore. If you need the tool and the bushings together, order Ridetech Part 11227299, which bundles both items at a savings over purchasing separately.

Installation Overview

These R-Joints press into the rear axle housing bore and replace the factory rubber bushing at the upper trailing arm pivot point. Installation requires a dedicated bushing press tool (Part 85000011). Do not attempt installation with a bench vise or improvised press, as uneven force will damage the housing bore or the R-Joint assembly.

• Verify axle housing bore diameter before ordering: most 1964-1977 A-Body and all 1978-1988 G-Body applications use a 1.85 in. bore. Some 1964 model year cars were built with a 1.375 in. bore. Measure your axle housing before placing the order.
• Install spacers onto the center pivot ball first, then press the R-Joint assembly into the bore
• New R-Joints will feel stiff: expect 75 to 90 in/lbs of breakaway torque until the assembly is broken in. This is normal and resolves after a few miles of driving
• Do NOT lubricate: the RTX10 composite cage is fully self-lubricating. Adding grease or oil will attract debris and degrade performance
• Recommended tools: Ridetech Part 85000011 bushing press tool, torque wrench, basic hand tools

Fitment: 1964-1977 GM A-Body and 1978-1988 GM G-Body

11227298 fits GM A-Body vehicles from 1964 through 1977 and GM G-Body vehicles from 1978 through 1988 across Buick, Chevrolet, GMC, Oldsmobile, and Pontiac nameplates. Confirm your axle housing bore diameter (must be 1.85 in.) before ordering. Some 1964 vehicles used a smaller 1.375 in. bore and are not compatible with this part.

Full Specifications

Warranty Information

Ridetech backs the 11227298 with a 1-year limited warranty from the date of purchase for the original purchaser. Note that Ridetech classifies bushings as a "normal wear" item, which means bushing wear is specifically excluded from warranty coverage. This is standard practice in the performance suspension industry for any component that contacts a rotating surface.

Under the federal Magnuson-Moss Warranty Act, installing aftermarket suspension components like these R-Joints does not void your vehicle's factory warranty. A vehicle manufacturer or dealer cannot void your factory powertrain or chassis warranty simply because you installed an aftermarket part, unless they can demonstrate that the specific aftermarket part directly caused the failure being claimed.

California Prop 65 Warning: This product contains nickel from 17-4 stainless steel, a chemical known to the State of California to cause cancer. For more information, visit www.p65warnings.ca.gov.

Compare: 11227298 Bushings Only vs. Part 11227299 Bundle

Ridetech offers two purchasing options for this R-Joint upgrade:

• 11227298: The R-Joint bushing pair with spacers only. Choose this if you already own the Ridetech bushing press tool or have access to one. This is the correct part if you are replacing a previously installed R-Joint set.
• Part 11227299: The complete bundle including the 11227298 bushings plus the Part 85000011 installation and removal tool. This is the recommended option for first-time installation. The bundle saves $35.00 over purchasing the bushings and tool separately.
• Part 85000011 ($80.00): The bushing removal and installation press tool sold separately. Required for installation. Do not reorder if you already have one from a previous Ridetech R-Joint installation.

About Ridetech

Ridetech is a suspension engineering company based in Jasper, Indiana, focused entirely on American muscle car and classic GM chassis development. Every component in their lineup is designed, engineered, and manufactured in the USA. Ridetech's R-Joint technology represents a complete rethinking of the traditional rubber bushing, replacing a compliance-prone OEM part with a precision ball-and-socket assembly engineered for performance suspension systems. The 11227298 is one example of Ridetech's approach: purpose-built hardware for specific platforms, made from materials that perform in real-world conditions without ongoing maintenance.

Frequently Asked Questions

Does the 11227298 fit my 1964 GM A-Body vehicle?
It depends on your axle housing bore diameter. This R-Joint housing has a 1.85 in. OD and requires a matching 1.85 in. bore in the axle housing. Most 1964 A-Body vehicles use the 1.85 in. bore, but some 1964 model year cars were built with a smaller 1.375 in. bore. You must physically measure your axle housing bore before ordering. If your bore is 1.375 in., this part will not fit without modification.

What tool do I need to install the 11227298?
Installation requires the Ridetech bushing press tool, Part 85000011 (Sold separately). This is not optional, it is a required tool for proper installation. Without it, you risk damaging the axle housing bore or the R-Joint assembly during press-in. If you need both the bushings and the tool, order Part 11227299 and save $35.00 over buying them separately.

Why are the new R-Joints so stiff when I first install them?
New R-Joints have a designed-in breakaway torque of 75 to 90 in/lbs. This stiffness is intentional and is part of how the RTX10 composite cage seats itself during initial use. After a few miles of normal driving, the joint will break in and move freely. Do not attempt to lubricate the joint to reduce initial stiffness, as lubricant will degrade the self-lubricating cage.

Do the 11227298 R-Joints need grease or lubrication?
No. The RTX10 composite cage in this assembly is self-lubricating by design. Applying grease, oil, or any lubricant is not recommended and will attract debris, contaminate the cage material, and reduce service life. Install them dry and leave them alone.

Does the 11227298 fit G-Body cars like the Monte Carlo and Cutlass Supreme?
Yes. This part fits all 1978-1988 GM G-Body applications including the Chevrolet Monte Carlo (1978-1988), Oldsmobile Cutlass Supreme (1978-1988), Buick Regal (1978-1987), GMC Caballero (1978-1987), Pontiac Grand Prix (1978-1987), and the other G-Body nameplates listed in the fitment table above. The 1.85 in. bore fitment caveat applies only to certain 1964 A-Body vehicles, not to G-Body cars.

Will installing the 11227298 void my factory warranty?
No. Under the federal Magnuson-Moss Warranty Act, an aftermarket suspension component cannot void your vehicle's factory warranty unless the manufacturer or dealer can prove that the specific part directly caused the failure being claimed. Installing the RID11227298 on a classic GM vehicle will not void any remaining factory or aftermarket drivetrain warranties.

What is the difference between the 11227298 and a standard polyurethane bushing upgrade?
A polyurethane bushing is still a compliant bushing: it reduces deflection compared to rubber but still twists and binds under load. The 11227298 uses a true ball-and-socket R-Joint design. The joint articulates freely in all axes with no compliance and no bind, regardless of ride height or suspension travel. For vehicles running coilovers, lowered springs, or performance alignment settings, R-Joints eliminate the bind that polyurethane bushings develop when the suspension moves through its range of motion.

How many R-Joints are included in 11227298, and are spacers included?
This kit includes two R-Joint bushing assemblies (one pair, covering both the driver and passenger side upper trailing arm pivot points) plus four R-Joint spacers. The spacers are installed onto the center pivot ball first, before pressing in the R-Joint assembly. Everything needed to complete the bushing replacement is included, with the exception of the press tool (Part 85000011).

What makes 17-4 stainless steel the right material for R-Joint housings?
17-4 stainless steel is a precipitation-hardened grade that combines high tensile strength with excellent corrosion resistance. Investment casting allows the complex R-Joint housing geometry to be produced with tight dimensional tolerances, which is critical for maintaining consistent press-fit engagement in the axle housing bore over the life of the part. The polished stainless ball surface minimizes friction against the RTX10 cage. This material combination is one reason Ridetech manufactures these R-Joints in-house in Jasper, Indiana, rather than sourcing them offshore.

Does 11227298 fit the GMC Sprint and GMC Caballero?
Yes. The GMC Sprint (1971-1972) rides on the GM A-Body platform and is covered by this part. The GMC Caballero (1978-1987) is the G-Body counterpart to the El Camino and is also a confirmed fitment. Both models appear in the fitment table above. The same 1.85 in. bore verification applies to the 1971-1972 Sprint if you have any reason to question the axle housing specification.