Billet Aluminum vs Steel Ball Joint Spacers: Which Is Right for Your Truck?
Billet aluminum or steel ball joint spacers? Compare strength, weight, corrosion resistance, and cost to choose the best leveling kit for your Silverado or Sierra.
Buy on AmazonBillet Aluminum vs Steel Ball Joint Spacers: Which Is Right for Your Truck?
When shopping for a front leveling kit for your Chevrolet Silverado or GMC Sierra, you'll encounter two main material options: billet aluminum and steel. Both work — but they're not the same, and the right choice depends on how you use your truck. Here's the complete comparison.
What "Billet" Actually Means
"Billet" refers to the manufacturing process, not just the material. Billet aluminum is machined from a solid block (billet) of high-strength aluminum alloy, typically 6061-T6. This process produces parts with excellent dimensional accuracy, consistent material properties throughout, and no internal voids or porosity that casting can introduce.
When you see "billet aluminum" on a leveling kit, it means CNC-machined from solid bar stock — not cast, not stamped.
Side-by-Side Comparison
| Property | Billet Aluminum | CNC Steel |
|---|---|---|
| Weight | ~65% lighter than steel | Heavier |
| Tensile Strength | ~45,000 psi (6061-T6) | ~75,000+ psi |
| Corrosion Resistance | Naturally oxidizes to form protective layer — no coating needed | Requires coating or plating to resist rust |
| Thermal Expansion | Higher — but irrelevant at suspension operating temps | Lower |
| Cost | Slightly higher material cost | Lower raw material cost |
| Machining Precision | Excellent — machines cleanly | Excellent — machines cleanly |
| Long-term Durability | Excellent — no rust risk | Excellent if coated, degrades if coating fails |
When to Choose Billet Aluminum
2007–2018 Silverado/Sierra 1500 owners who want:
- Reduced unsprung weight (improves suspension response)
- No rust risk in salt-belt states or humid climates
- A clean, finished appearance under the hood
The ZNZNZZ Billet Aluminum Ball Joint Spacers are specifically designed for the 2007–2018 Chevrolet Silverado 1500 and GMC Sierra 1500 (2WD/4WD). The 2-inch front leveling spacers are CNC-machined from high-strength billet aluminum and include all mounting hardware.
Best for: Drivers in wet climates, salt-belt states, or anyone who prioritizes long-term corrosion resistance.
When to Choose CNC Steel
1988–2024 Silverado/Sierra/Tahoe/Yukon/Escalade owners (broader fitment range) who want:
- Maximum load-bearing capacity for heavy towing or payload
- A proven material used in OEM suspension components
- Wide fitment across multiple model years
The ZNZNZZ UCA Ball Joint Spacers use heavy-duty CNC-machined steel and cover an enormous range: Chevrolet, GMC, and Cadillac trucks and SUVs from 1988 to 2024.
Best for: Truck owners with heavier use cases, or those with older models not covered by the aluminum kit.
The Weight Question: Does It Actually Matter?
Billet aluminum is roughly 65% lighter than the equivalent steel piece. For a small spacer, the absolute weight difference might be 80–150 grams per side. In isolation, that sounds insignificant.
But unsprung weight — mass that moves with the wheel rather than the chassis — directly affects suspension response and road feel. Less unsprung weight means:
- Faster suspension response to road inputs
- Improved tire contact patch consistency
- Slightly reduced rotational inertia
For a daily driver on highway and light off-road, the difference is subtle but measurable. For a dedicated sport truck or performance application, it's meaningful.
The Corrosion Question: Will Steel Rust?
Quality CNC-machined steel spacers are typically coated or finished to resist corrosion. The risk is what happens if that coating is damaged — either during installation, or over years of exposure to road salt, moisture, and gravel.
Aluminum doesn't rust. Aluminum oxide forms naturally on the surface and actually protects the base metal. In salt-belt states like the Northeast and Midwest where roads are heavily salted in winter, this is a genuine long-term advantage.
Which Kit Fits Your Year?
| Kit | Fitment |
|---|---|
| ZNZNZZ Billet Aluminum (ASIN: B0GDY3T36V) | 2007–2018 Silverado 1500 / Sierra 1500 (2WD/4WD) |
| ZNZNZZ UCA Steel (ASIN: B0GF2DFLRB) | 1988–2024 Silverado/Sierra/Tahoe/Suburban/Blazer/Astro/Express/Yukon/Safari/Savana/Escalade |
If you have a 2019+ Silverado or Sierra 1500, the UCA Ball Joint Spacers kit is the correct choice — the billet kit does not fit 2019+ models.
Frequently Asked Questions
Q: Can I use billet aluminum spacers for off-road use? A: Yes. High-strength 6061-T6 aluminum is used in aerospace and high-performance automotive applications. It handles off-road stress well.
Q: Do aluminum spacers require any special hardware? A: No. The ZNZNZZ Billet kit includes all mounting hardware compatible with the OEM installation points.
Q: Which has better resale value — aluminum or steel? A: Both are functional lifetime parts. Resale value depends more on installation quality and truck condition than spacer material.
Q: Can I mix materials — aluminum on one side, steel on the other? A: Not recommended. Use matched components on both sides to ensure equal lift height and consistent suspension geometry.
Both kits are available on Amazon with Prime shipping.