 I have been driving Hondas for 30 years.I purchased the Mazda 2 years ago.The turbo just went out and Mazda won't honior the warrantly because there is "sludge" in my engine.The Mazda dealership told me to replace the entire engine at a cost of $9000.I have 60,000 miles on it.Regular maintenance and use synthetic oil but since I did not have my oil changes done at the dealership the dealership won't cover it either.Also, I bought it used and did think to ask for copies of the oil changes from the previous owner and without those, I can't prove the oil was changed every 3,000 miles.