Thinking about buying a used GWM Cannon (2020–2023) in New Zealand? We've documented 7 known faults for this model spanning fluid leaks, engine, and transmission. Each researched and verified before it's published. The most serious issues here are rated critical. Two are set out in full below — the rest, with the symptoms, repair costs and checks for each, are free with an account.
7
Documented faults
Critical
Most serious
$350–$3,800
Typical repair
3
Systems covered
Known GWM Cannon faults
Every fault below is documented specifically for this model — researched and verified before it’s published.
01Fuel filter O-ring leak — fire risk (recall REC-006123)
CriticalOccasionalFluid Leaks $150–$600 to fix
GWM recalled 2,872 Cannon utes built in 2023 because the wrong lubricant was applied to the diesel fuel filter O-ring at the factory, letting the seal degrade and diesel leak from the filter housing — a fire risk near an ignition source. The fix is a free O-ring replacement at a GWM dealer under Australian recall REC-006123 (a matching NZ campaign ran through GWM NZ dealers); recall rectification does not expire, but an unrepaired car is a genuine hazard. Any 2023-build Cannon should have dealer paperwork showing the recall was completed.
Symptoms to notice
Diesel smell around engine bay
Wet/oily film or drips around fuel filter housing
Fuel stains on driveway under engine
Recall letter received but never actioned
What to check
Open the bonnet cold and look and sniff around the diesel fuel filter housing for wetness, staining or diesel smell. Ask the seller for the GWM dealer invoice or service-book stamp showing the fuel-filter O-ring recall was completed, then confirm by phoning a GWM dealer with the VIN.
Where to look: Engine bay — diesel fuel filter housing
Ask the seller
“Has the 2023 fuel filter recall (REC-006123) been carried out on this VIN?”
“Can you show me the dealer paperwork for the recall repair?”
“Have you ever noticed a diesel smell or leak?”
02Rear Differential Output Shaft Oil Seal Leak
MajorOccasionalFluid Leaks $350–$1,200 to fix
The rear differential pinion and output shaft oil seals on the GWM Cannon have been identified as a recurring leak point, particularly on vehicles operated in off-road conditions or subject to water crossings. The seals degrade prematurely under heat cycling and contamination ingress, allowing gear oil to weep from the differential casing. If undetected, continued operation with low differential oil risks bearing and gear surface damage requiring differential rebuild or replacement.
Symptoms to notice
Oil staining or wet patch beneath the rear differential
Gear oil smell from the rear axle area
Differential oil level below minimum on check
Whining or grinding from the rear diff under load if oil has been lost
What to check
Inspect the rear differential casing and output shaft flanges for oil weeping or staining. Check the differential oil level via the filler plug. Look for fresh oil on the driveshaft CVJ boots near the diff flanges. Any off-road-used example should have all diffs and transfer case inspected.
Where to look: Rear differential, output shaft seals and pinion seal
Ask the seller
“Has the vehicle been used off-road or in water crossings?”
“Have the differential oils been changed since purchase?”
“Has any leaking been noticed under the rear axle?”
EngineMajor
TransmissionMajor
EngineMajor
EngineMajor
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5 more documented faults on the GWM Cannon
Symptoms, what to check, where to look and what to ask the seller — for every fault above. Free with an account, no card needed. One account covers one vehicle, so make it the car you’re actually looking at.
This page covers the model. Enter the plate of the actual car you’re looking at and see its year, engine, safety rating and register flags — free, no account needed.
Like any used car, it depends on the specific example and its service history. Across the 7 documented faults for the GWM Cannon, the recurring problem areas are fluid leaks, engine, and transmission. A GWM Cannon with a full service history and no signs of the issues listed on this page can be a sound buy but each one needs to be checked individually before you commit.
What are the most common problems with a used GWM Cannon?
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We've catalogued 7 known faults for the GWM Cannon, covering fluid leaks, engine, and transmission. Two are written out in full on this page. The rest — with the symptoms to notice, what to inspect, and typical repair costs for each — are free once you create an account.
How much do repairs cost on a GWM Cannon?
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Most single repairs on the GWM Cannon fall between $350–$3,800 at NZ independent-workshop rates. Some of the 7 documented faults cost less and a few cost considerably more, and no one car needs them all. Knowing which ones to look for before you view is what lets you negotiate the price down or walk away.
Should I get a pre-purchase inspection on a GWM Cannon?
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Yes. A GWM Cannon inspection focused on its known weak points is the single best way to avoid an expensive mistake. KickTyres gives you a guided, model-specific inspection plus a market valuation and negotiation figure for $17.90 far less than the cost of missing one of the faults on this page.