Stopping That Annoying Knock in Your Silverado's Front End

How to Fix Control Arm Issue

For 2020 Chevrolet Silverado owners, addressing concerns related to the front suspension, particularly control arms, is crucial for maintaining ride quality and safety. While direct failures of the control arm itself are less commonly reported for this model year, owner discussions frequently connect suspension noises and handling issues to worn components within the front end, such as ball joints (which are integral to the control arm assembly) and motor mounts. The solution often involves inspection and targeted replacement. As one owner advised regarding a general suspension upgrade, "I highly recommend you get a proper lift and some better upper control arms though." (source)

Symptoms

Owners describe a range of symptoms that can point to issues within the front suspension system, where the control arms are a key component. The most frequently reported symptom is a persistent, annoying noise. This often manifests as a knocking, tapping, or clunking sound that seems to emanate from the front end or floorboard area, especially when going over bumps, during acceleration, or when turning.

These noises are more than just a minor annoyance; they are direct indicators of wear. As one owner detailed after a long diagnostic journey, "After months of hearing a knocking/tapping sound coming from the floorboard area, I finally think the issue is solved." (source) This highlights how elusive and persistent these suspension-related sounds can be, often requiring thorough investigation to pinpoint the exact source, which may not always be the control arm itself but a related component.

In more severe cases of wear in the front suspension linkage—which includes the ball joints housed in the control arms—you may experience vague steering, a feeling of the front end "wandering" or being loose, or uneven tire wear. While less directly cited in the provided quotes for the 2020 model, these are classic signs of failing ball joints or worn control arm bushings. The symptom of "annoyance" is a universal summary, but it's the specific noise and its behavior that provides the critical diagnostic clue.

Most Likely Cause

Based on analysis of owner reports, the most likely cause of symptoms commonly misattributed to a "control arm issue" on the 2020 Silverado is wear in interconnected front-end components, specifically failing motor mounts and worn ball joints. It is critical to understand that a noise from the front end does not automatically condemn the control arm. The control arm is a structural piece; the issues arise from the parts attached to it or other engine/suspension components.

Owner experiences clearly point to motor mounts as a frequent culprit for knocking noises. One owner's headline stated the solution plainly: "Months of Knocking Noise Finally Solved – Bad Motor Mounts." (source) When engine mounts degrade, they allow excessive engine movement, which can transmit metallic knocking sounds through the chassis that are easily mistaken for suspension noise. Simultaneously, the ball joint, which is the pivotal connection between the control arm and the steering knuckle, is a common wear item. As it wears out, it creates play and a distinct clunking noise during suspension movement. Therefore, the "cause" is the failure of these specific wear items within the system, not necessarily the control arm casting itself.

How to Diagnose

Accurate diagnosis is essential to avoid replacing expensive parts unnecessarily. You will need a few basic tools: a sturdy jack, jack stands, a pry bar (or large screwdriver), a flashlight, and a helper.

First, perform a visual inspection. With the truck parked on level ground and the parking brake engaged, look at the control arms, ball joint boots, and motor mounts. Check for any obvious damage, severe rust, or torn rubber boots on the ball joints. A torn boot means contamination has entered the joint, leading to rapid wear. Next, conduct a static "pry" test. Safely lift the front of the truck and support it with jack stands under the frame, allowing the front wheels to hang freely. Grip the tire at the top and bottom and try to rock it in and out. Excessive play here can indicate worn wheel bearings or ball joints. To isolate the ball joint, use your pry bar to lift up on the tire. If you see movement between the steering knuckle and the control arm where the ball joint is seated, the joint is likely worn.

For motor mounts, the test is done with the engine running. Have your helper sit in the truck with their foot firmly on the brake. Open the hood and, while they cycle the transmission from Park to Drive to Reverse (with brake held), watch the engine. If it lifts excessively (more than an inch or so) or you hear a loud clunk/thud during the shift, the motor mounts are probably bad. You can also visually inspect the mounts for cracked, collapsed, or separated rubber. Finally, for the most accurate assessment of control arm bushings, use a large pry bar to lever the control arm itself, looking for movement between the metal bushing sleeve and the control arm or frame bracket. Any significant, visible movement indicates bushing failure.

Step-by-Step Fix

Replacing a worn ball joint or control arm assembly is a common DIY repair for those with mechanical aptitude and proper tools. Warning: Always consult a factory service manual for torque specifications and precise procedures for your 2020 Silverado. These steps provide a general overview.

1. Safety First: Park on a flat, solid surface. Engage the parking brake and place wheel chocks behind the rear tires. Loosen the lug nuts on the front wheel you'll be working on before lifting the truck.
2. Lift and Secure: Using a floor jack placed at the manufacturer's specified front lift point (usually on the frame rail), lift the front of the truck. Place a high-quality jack stand under the frame for safety. The wheel should be off the ground.
3. Remove Wheel and Brake Components: Remove the lug nuts and take off the wheel. For better access, you may need to remove the brake caliper (hang it from the suspension with wire, do not let it dangle by the hose) and the brake rotor.
4. Separate the Ball Joint: This is the critical step. You need to separate the ball joint stud from the steering knuckle. Using a pickle fork or a ball joint separator tool, drive the wedge between the knuckle and the ball joint stud. It will take significant force. As one owner working on a different issue demonstrated, methodical troubleshooting is key: "Found some chaffed wires... I’ve checked power and grounds again with a multimeter and a power probe." (source) Apply the same systematic approach here.
5. Unbolt the Control Arm: Once the ball joint is free, you can unbolt the control arm from the frame. There will typically be two bolts at the inner bushing side. Note their orientation. If you are only replacing a press-in ball joint, you can now take the control arm to a bench and use a ball joint press kit to remove the old one and install the new.
6. Install New Component: If replacing the entire control arm assembly (which comes with new bushings and a pre-installed ball joint), simply position it and install the new frame bolts hand-tight. Guide the new ball joint stud into the steering knuckle.
7. Reassemble: Install the ball joint nut and tighten it to the manufacturer's specification. Then, torque the control arm frame bolts to spec. Reinstall the brake rotor, caliper, and wheel.
8. Lower and Final Torque: Lower the truck so the tires are lightly loaded on the ground (full vehicle weight on suspension). This is when you must perform the final torque on all suspension bolts, especially the ball joint nut and control arm bolts, to the exact values specified. This ensures the bushings are not pre-loaded incorrectly.
9. Alignment: This step is non-negotiable. Any time you disconnect a ball joint or replace a control arm, you have altered the front suspension geometry. You must take your truck for a professional wheel alignment immediately after the repair.

Parts and Tools Needed

• Parts:
  • Upper or Lower Control Arm Assembly (often includes ball joint and bushings). Part numbers vary by trim and drivetrain (2WD vs 4WD). Common aftermarket brands include Moog, ACDelco (GM OEM), and Mevotech.
  • Alternative: Press-in Ball Joint (if replacing only the joint). Ensure it matches your specific control arm.
  • New Cotter Pin for the ball joint castle nut.
• Tools:
  • Floor Jack and Jack Stands (rated for the truck's weight)
  • Lug Wrench / Impact Wrench
  • Socket Set (metric, typically 10mm-24mm)
  • Torque Wrench (critical for final specs)
  • Ball Joint Separator Tool (pickle fork or clamp-style)
  • Pry Bar
  • Hammer
  • If pressing ball joints: Ball Joint Press Kit
  • Penetrating Oil (like PB Blaster)

Real Owner Costs

Costs can vary widely based on whether you DIY, use aftermarket parts, or go to a dealer. The quotes provided highlight owner perspectives on value and repair complexity.

For a DIY repair using quality aftermarket control arms, expect to spend $150 to $400 per side for the parts. Your total cost is just the parts, assuming you have the tools. This is the most economical route, as one owner hinted at when discussing transmission repairs, suggesting an "upgraded remanufactured unit" as a cost-effective solution over a dealer part (source).

Taking your truck to an independent repair shop will include parts and labor. For replacing one control arm assembly (including an alignment), expect a total bill between $500 and $900 per side. The dealership will be at the highest end of this range, often exceeding $1,000 per side for parts and labor. These costs contribute to the broader sentiment some owners have about vehicle expenses. As one owner expressed about truck prices, "I believe that these prices are far beyond insane and are totally out of control." (source) While about MSRP, it reflects the frustration with high automotive costs, including repairs.

If the diagnosis points only to a press-in ball joint, costs are lower. A ball joint part might be $50-$100, with shop labor around 1.5-2 hours plus alignment, leading to a total cost of $250 to $500.

Prevention

Preventing premature wear of suspension components like ball joints and control arm bushings revolves around driving habits and maintenance. Avoid harsh impacts with potholes, curbs, and speed bumps whenever possible. These shocks put tremendous stress on the front end. If you frequently drive on rough roads or off-road, more frequent inspections are necessary.

Regular visual inspections are your best preventative tool. When you rotate your tires every 5,000-7,500 miles, take a moment to look at the ball joint boots for tears and the control arm bushings for cracks or excessive sagging. Listen for new noises and address them promptly; a small clunk today can lead to a dangerous failure and more expensive damage later. Keeping the front end clean of heavy mud and road salt can also help prolong the life of rubber components.

What Owners Say

Real experiences from CHEVROLET owners:

Success Stories

"Found some chaffed wires going to the fuel pump control module got those fixed then the truck wouldn’t do anything again no crank no start. I’ve checked power and grounds again with a multimeter and a power probe i have good power and ground at the fuel pump,starter,12.3v on battery i unplugged the fpcm to see if it would turn over and it still would not(to see if the fpcm was blown)." — Own-Yam-5606 (source)

Owner Experiences

"From what I gather it’s a combination of problems (lack of proper maintenance and weak converter). Instead of getting one from the local scrap yard I’m looking at getting an upgraded remanufactured unit." — open_road_toad (source)

"I’ve read about all the horror stories regarding that particular transmission. From what I gather it’s a combination of problems (lack of proper maintenance and weak converter)." — open_road_toad (source)

"I was driving and my truck randomly lost engine power. Got it towed to a shop they checked grounds,power wires,relays,fuses about everything they could they said,so they told me they couldn’t fix it it has dash power,lights come on just won’t turn over,you can apply power to the starter and it’ll spin over.Anyway got it home and after it sat for a while it started and would die after driving a few feet." — Own-Yam-5606 (source)

Real Repair Costs

"I believe that these prices are far beyond insane and are totally out of control. There’s not a 1/2 pickup on the planet that should have a $96K sticker!" — SadDonkey5832 (source)

FAQ

Q: How long does it take to replace a control arm? A: For a experienced DIYer with the right tools, replacing one control arm can take 2 to 4 hours, not including the time for a professional alignment. A shop will typically book 1.5 to 2.5 hours of labor for the job.

Q: Can I drive with a knocking noise in the front end? A: It is not recommended. A knocking noise indicates a worn component with excessive play. Driving on a severely worn ball joint can lead to catastrophic failure, where the joint separates and causes you to lose control of the vehicle. Have it diagnosed as soon as possible.

Q: Is this a common issue on the 2020 Silverado? A: Worn ball joints and motor mounts are common wear items on any truck over time and mileage, not a specific defect unique to the 2020 model. The frequency of owner reports about knocking noises suggests these are components that often require attention as the truck ages. The control arm itself is not a common failure point.

Q: DIY vs mechanic – what's recommended for this repair? A: This is a high-intermediate DIY job. It requires significant force, proper torque procedures, and must end with a professional alignment. If you are comfortable with suspension work, have a good tool set, and a torque wrench, you can save considerable money. If you are unsure about any step, especially separating the ball joint or achieving correct torque specs, hiring a professional is the safer choice to ensure your truck's safety and handling.

Q: Do I need an alignment after replacing a control arm? A: Absolutely yes. Replacing a control arm or ball joint directly changes the angles of your front suspension (camber and caster). Driving without a proper alignment will cause rapid, uneven tire wear and may affect handling.

Q: Could the noise be something else besides a control arm or ball joint? A: Definitely. As evidenced by owner reports, bad motor mounts are a prime suspect for knocking noises. Other possibilities include worn sway bar end links, loose strut mounts, or a failing CV axle (on 4WD models). A systematic diagnosis is crucial to avoid misdiagnosis.