Recently been posted on the Captiva forum, same applies to Antara.
There is a case of a 6 speed6T50 Automatic Transmission failure on a 2012 Captiva. Gearbox totally failed due to casing fracture. Cost to repair circa £10,000.00 from Vauxhall Main Dealer. Luckily for the owner he has the extended dealer warranty. This is the first case in UK of a 6T50 failure reported on a forum, normally its the earlier 6T40 and 6T45's that fail. Owner has only done 35,000 miles till failure.
Chevrolet Captiva LTZ ( 2014 )