Adjusting Rear Camber on Your Car with Shocks: A DIY Guide Using a Caster Camber Tool

It can be frustrating when your car mechanic tells you that you need new shocks to fix a rear camber issue, especially when it seems like there should be a simpler solution. This was exactly the situation I faced with my 2011 Cadillac CTS Wagon. After a four-wheel alignment, I was informed that the right rear camber was out of specification. The mechanic’s diagnosis? Replace both rear shocks to restore ride height and correct the camber. Trusting his expertise, I nearly made an expensive and unnecessary mistake.

Upon removing the original shocks and comparing them to brand new OEM GM replacements, I found no discernible difference. The suspicion grew, and after installing the new shocks, the car’s rear ride height remained unchanged, and the camber issue persisted. This led me to online research, where I quickly discovered the reality: rear camber on many cars, including the Cadillac CTS, is indeed adjustable and doesn’t necessarily require shock replacement. The key is using the correct tool – a caster camber tool.

It turns out that rear camber adjustment is achieved by manipulating the lower control arm within its slotted bracket. This realization, combined with information from online forums and automotive repair websites, empowered me to take matters into my own hands. I found a helpful thread detailing a clone of the J-45845 caster/camber adjusting tool, specifically designed for this type of adjustment. Armed with this knowledge, I decided to fabricate my own tool.

Returning to the same mechanic with my homemade caster camber tool, we successfully adjusted the rear camber back to the factory specifications. This experience saved me unnecessary expenses and highlighted the importance of understanding your vehicle’s suspension system.

This article aims to share the information I gathered and guide anyone facing similar rear camber issues, particularly those told to replace shocks without exploring adjustment options. It’s crucial to understand that while shocks play a role in ride height and suspension performance, they are not the primary adjustment point for camber in many modern vehicles.

Understanding Rear Camber and Why It Matters

Camber refers to the angle of your car’s wheels relative to the vertical axis when viewed from the front or rear. Incorrect camber can lead to several problems:

Uneven Tire Wear: Excessive positive or negative camber causes tires to wear out prematurely on one side.
Poor Handling: Misaligned camber can affect steering response and overall vehicle stability.
Suspension Issues: While not always caused by shocks, incorrect camber can sometimes indicate other suspension problems.

The Role of a Caster Camber Tool

A caster camber tool is designed to provide leverage and precise movement to adjust these angles. For vehicles with adjustable control arm brackets, like the Cadillac CTS, this tool is essential for making accurate camber adjustments. It allows mechanics and DIYers to shift the control arm within its slotted mount, effectively changing the camber angle without needing to replace suspension components like shocks unnecessarily.

Identifying the Right Tool: J-45845 and Alternatives

The original thread I found referenced the J-45845 caster/camber adjusting tool. This is a professional-grade tool designed for General Motors vehicles and is available from various suppliers.

You can find the J-45845 tool at retailers like Freedom Racing or consider universal caster camber tools, such as the Specialty Products Alignment Caster Camber Tool 83785, available at AutoZone. These tools serve the same purpose: providing the necessary force and control to adjust the control arm and, consequently, the camber angle.

DIY Caster Camber Tool Fabrication

For those who prefer a more hands-on approach, fabricating a DIY caster camber tool is possible. Inspired by the forum thread, I created my own tool, which proved effective in adjusting the rear camber on my CTS Wagon. Here are images detailing the tool I made:

Conclusion: Don’t Immediately Assume Shock Replacement for Camber Issues

Before agreeing to shock replacement for a rear camber issue, especially if your car has shocks and adjustable control arms, investigate whether a simple camber adjustment is possible. Equipping yourself with a caster camber tool, whether purchased or homemade, can potentially save you significant money and unnecessary repairs. Always consult your vehicle’s service manual and consider seeking a second opinion from a qualified alignment specialist to ensure the correct diagnosis and repair procedure.

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