Australian Car Repair Issues? Ask an Auto Mechanic for Answers ASAP
The thermostat housing is at the back of the engine, that's why it is a labour intensive job.
Alloytec V6 is known for weeping welch plugs from the cylinder heads above the valley area of the cylinder block.
When this happens coolant appears to leaking from water pump or thermostat housing.
The drivetrain light is for engine and transmission, so it probably is from engine overheating.
What codes are set in the PCM?
Do you need any further help?
I hope my advice has been of assistance to you.