CriticalCommonEngine

Holden Commodore: ZB 2.0 turbo-diesel runs a timing belt due at 10 years or 120,000 km

ZB 2.0 turbo-diesel runs a timing belt due at 10 years or 120,000 km is a common engine fault on the Holden Commodore on the 2018–2020 cars, and we rate it critical. Putting it right costs $1,100 to $2,200 at New Zealand independent workshop rates. Below is what goes wrong, the symptoms to notice on a test drive, where to look, and what to ask the seller before you hand over any money. It is one of 51 documented faults on the Holden Commodore.

Vehicle: Holden Commodore
Engine: 2.0L
Years: 2018–2020
Fuel: diesel
System: Engine

This page covers the Holden Commodore as a model. Some faults only affect particular engines or build years — enter a plate below to narrow the list to one car.

All Holden Commodore faults51 documented faults on this model

What you are looking at

No photograph available

We do not hold a verified photograph of the Timing belt or Turbocharger yet. We would rather show none than show a picture of a different part.

What goes wrong

Unlike the petrol ZB, the 2.0 litre turbo-diesel Commodore drives its camshafts with a rubber timing belt, and Holden's own MY18 service and warranty booklet calls for that belt to be replaced at 10 years or 120,000 kilometres, whichever comes first. If the belt lets go the pistons and valves meet and the engine is finished, and with Holden wound up here the parts for this engine are neither cheap nor quick to source. Most of these cars are now past the kilometre trigger, and because the belt lives behind a cover there is nothing to see and no warning noise - the only evidence is paperwork. A ZB diesel with no belt receipt should be priced as though the belt is due today.

What you would notice

No symptom at all until the belt fails
Rattle or chirp from the timing cover end of the engine
Engine stops dead while driving and will not restart
Squeal from the timing end of the engine on a cold start

How to check it

Where to look. Behind a plastic cover on the right-hand end of the transversely mounted engine, next to the inner guard.

This is a paperwork check first and a mechanical one second.
Ask the seller to show you a receipt that names the timing belt, the tensioner and the water pump, with a date and an odometer reading on it, because a verbal 'I think it has been done' is worth nothing here.
Read the odometer and the build date on the plate in the door frame and work out whether the car has passed 120,000 kilometres or ten years.
Check the service book for a belt entry and look through the glovebox and the boot for old invoices.
With the bonnet up, look for a workshop sticker on the timing cover or the slam panel recording a belt change.
Ask whether the car has done mostly open road or stop-start work, and ask when it was last fully serviced.
If a workshop inspection is possible: have a mechanic inspect the belt condition through the cover and confirm the tensioner and water pump were changed with it.

Parts involved: Timing belt, Turbocharger.

What it costs to put right

$1,100 to $2,200 at New Zealand independent workshop rates. That is for this job on its own, not for the car.

An estimate, in NZD, for the repair as normally carried out. What a specific car costs depends on which part has failed and what it damaged on the way — treat this as the floor for a negotiation, not a quote.

Ask the seller

“Has the timing belt been replaced, and can I see the receipt?”
“Were the tensioner and water pump done at the same time?”
“What was the odometer reading when the belt was done?”
“When was the last full service?”

Now check the Holden Commodore you are actually looking at

Everything above is true of the model, and it is free. What it does not tell you is whether THIS car has been looked after: its odometer history and whether the reading has ever gone backwards, whether there is still money owing on it, whether it has been reported stolen, how many owners it has had and what it is really worth today. That comes from the official records for that plate. Enter the plate for the free details, or get the full history and a market valuation from $13.49.

Not sure what you would be paying for? See what a full KickTyres check includes.

Where this comes from

The failure described above is documented in the sources below. The inspection instructions and the cost estimate are KickTyres’ own interpretation of them.

Holden MY18 ZB Commodore Service & Warranty Booklet (holden.com.au) - timing belt replacement at 10 years or 120,000 km
ReDriven 'Used Holden ZB Commodore review' - 120,000 km timing belt requirement and parts availability warning
JustCommodores forum thread 'ZB 2 litre...timing belt or chain?'

Holden Commodore buyer questions

Is zb 2.0 turbo-diesel runs a timing belt due at 10 years or 120,000 km serious on a Holden Commodore?

We rate it critical and common on the Holden Commodore. Unlike the petrol ZB, the 2.0 litre turbo-diesel Commodore drives its camshafts with a rubber timing belt, and Holden's own MY18 service and warranty booklet calls for that belt to be replaced at 10 years or 120,000 kilometres, whichever comes first. If the belt lets go the pistons and valves meet and the engine is finished, and with Holden wound up here the parts for this engine are neither cheap nor quick to source. Most of these cars are now past the kilometre trigger, and because the belt lives behind a cover there is nothing to see and no warning noise - the only evidence is paperwork. A ZB diesel with no belt receipt should be priced as though the belt is due today.

How much does it cost to fix on a Holden Commodore?

$1,100 to $2,200 at New Zealand independent workshop rates. That figure is for this job on its own. A car showing the symptoms on this page is usually worth either walking away from or negotiating down by at least the repair figure.

Which Holden Commodore years are affected?

Our research records this fault on the 2018–2020 Holden Commodore. Build dates move around, especially on imported cars, so treat the range as the years to look hardest at rather than a guarantee either way. The official records tell you the exact build and first registration date for the car in front of you.

How do I check for it before I buy?

This is a paperwork check first and a mechanical one second. Ask the seller to show you a receipt that names the timing belt, the tensioner and the water pump, with a date and an odometer reading on it, because a verbal 'I think it has been done' is worth nothing here. Read the odometer and the build date on the plate in the door frame and work out whether the car has passed 120,000 kilometres or ten years. Check the service book for a belt entry and look through the glovebox and the boot for old invoices. With the bonnet up, look for a workshop sticker on the timing cover or the slam panel recording a belt change. Ask whether the car has done mostly open road or stop-start work, and ask when it was last fully serviced. If a workshop inspection is possible: have a mechanic inspect the belt condition through the cover and confirm the tensioner and water pump were changed with it. Look here: Behind a plastic cover on the right-hand end of the transversely mounted engine, next to the inner guard.