Cheap vs. Nasty: A Mechanic’s Guide to Chinese EV Undercarriage Quality

Tim Bond
23 hours ago
2 min read

Key Facts:

The "Micron" Test: Why some Chinese brands have paint 30% thinner than a Mazda, and why you need ceramic coating.
The Rust Trap: The specific sub-frame areas on the GWM Ora and MG4 that need checking before you drive on the beach.
Bush-Bashing: Why the suspension bushes on the Chery Omoda 5 are struggling with Australian potholes.
The "Galvanised" Truth: Which brands are dipping their chassis properly, and which are just spraying it black.

They look fantastic in the showroom. LED lights, soft-touch dashes, and massive touchscreens. But Australian roads—and Australian oceans—are unforgiving.

Let's strip back the plastic covers to look at the Chinese EV Quality Australia reality.

Here is what we found.

1. Paint Thickness (The "Orange Peel" Factor)

Benchmark (Mazda/Toyota): 110 – 130 microns.
BYD Atto 3: 90 – 100 microns. (Acceptable, but thin. scratches easily).
GWM Ora: 80 – 90 microns. (Very thin. Bird droppings will etch this in hours).

Of course, before we are labelled 'Chinese Biased' it should be noted that similar complaints about thin paint, soft clear coat, and limited underbody protection have also been raised for European, Japanese, and Korean brands in recent years, especially on cost‑pressed models.

The Fix: If you buy a GWM or BYD, factor in $1,000 for a high-quality Ceramic Coat immediately. It’s not a luxury; it’s a protective necessity.

2. Rust Protection (The Coastal Killer)

Underneath, most modern cars are "e-coated" (dipped in rust preventative).

MG4: Good coverage on the main rails, but the sub-frame welds showed light surface oxidation on our 10,000km test car.
BYD: excellent underbody sealing. They use a heavy rubberised coating in the wheel arches which also dampens road noise.
GWM: Sparse application. Large sections of the floorpan are painted metal with no stone-chip protection.

The Fix: If you live within 5km of the ocean, pay the $600 for an aftermarket "Chemical Rust Proofing" spray.

3. Suspension Components (The Pothole Test)

This is where Chinese EV Quality Australia shows the biggest variance.

Chery Omoda E5: Reports of rear axle issues have plagued this platform. The control arms look thin compared to a Toyota RAV4. We advise caution for rural drivers on corrugated roads.
BYD Shark 6: Built like a tank. The suspension components are over-engineered, clearly targeting the Ranger/Hilux crowd.

Chinese EV Quality: The Verdict

The gap between "Chinese Cars" is widening.

Top Tier (BYD): Build quality is now rivalling the Japanese.
Mid Tier (MG/GWM): mechanically sound, but paint and finish are budget-grade.
Low Tier (New Startups): Suspension and rust-proofing are not yet "Australia Ready."

Verdict: Don't be afraid of the badge, but do your homework. A $50,000 BYD is built very differently to a $35,000 budget hatch.

FAQs

Does a thin paint job affect resale value?

Yes. If the clear coat fails (peels) in 5 years, the car is worthless. Keep it waxed or ceramic coated.

Should I rust proof my EV?

In Australia? Yes. Especially if it's a cheaper model. The factory protection is often designed for European winters (salt roads), not Australian summers (salt spray + humidity).