talagang maingay ang diesel engines. mas-maingay kung direct-injection engine (versus one that has pre-combustion chamber). remember that diesel engines have very high compression ratio.

however, you can reduce the noise inside the cabin by installing sound proofing materials. a combination of bitumen materials (dynamat or wurth) plus foam sound deadener (wurth sound foam) along the firewall, doors, floor, ceiling will do the trick.