US judge Charles Breyer overruled objections to grant final approval for the 3.0-litre Volkswagen diesel-emissions settlement on Thursday.

The deal — which will see VW pay up to $1.2bn to repurchase or fix around 75,000 3.0-litre VW, Audi and Porsche cars — already received preliminary approval in February. A larger settlement involving half-a-million 2.0-litre cars was already approved.

In total, VW will pay about nearly $24bn to buy back cars and compensate owners in the US and Canada, after admitting it installed software to cheat emissions tests in a decade-long conspiracy.

The company’s lawyer Robert Giuffra said it would be a “milestone” for VW to receive final approval, as every affected VW diesel-engine car in the US — nearly 600,000 — have now been legally addressed. Car owners eligible for a buyback still have more than a year to decide whether to keep their cars or sell them back.

Various objectors had sought extra compensation for lessees, questioned why the US Environmental Protection Agency should receive penalty payments or claimed that VW’s “fix” – a modification to reduce pollution – had hurt fuel economy.

The judge also approved a settlement related to Bosch, the German car component supplier whose software VW used in its emissions cheating. The private company previously agreed to pay $327.5m to resolve claims while denying any wrongdoing.

Car owners will receive between $200 and $1,500 each from the Bosch settlement, depending on the make and model of their car.

Judge Breyer, during a hearing on Thursday that lasted more than two-and-a-half hours, also offered a robust defence of the way he handled the case, following complaints about why it is still unclear why US regulators did not detect the cheating for years.

The judge said a “deep evidentiary probe” into how the cheating occurred was not his priority. He has emphasised from the start the need to get the polluting cars off of US roads and to compensate owners deceived by VW marketing. “That was the goal,” he said. “It was limited in that scope, by design.”