Ford Motor Company research claims to show that attention to powertrain refinement levels and engine sound quality is making a difference to customers. Engineers have made a "significant" number of improvements in noise, vibration and harshness (NVH) on many of the company's 2002 engines, including the 5.4-litre Triton V8 and the 3.0-litre Duratec V6. Ford also is focusing on NVH levels in future vehicles such as the new Lincoln Aviator with 4.6-litre InTech V8.