Bad customer service and retention

I took my GWM Steed 5 Double cab in for repairs as it was over heating. The mileage was 45000km. 3 years old.<br> Just out of warrantee. I understand that they are doing what was signed for, but no sorry or could we help with some discount. It took them 3 weeks to come back to me with an answer. Now only to tell me that they want to replace the radiator and the head gasket. Why would they do that? They haven't even opened the engine up or done the compression test to see if the fault lies with the head gasket. R16'000 before tax.