To evaluate the engine wear protection provided by SAE 5W-30 engine oils, two SAE 5W-30 engine oils containing different VI improvers and having different high-temperature high-shear-rate viscosities were tested in matched pairs of cars with 3.8 L V-6 and 2.3 L I-4 engines. The tests were run on Road-Simulation-Dynamometers using a cycle which simulated a combination of urban and highway driving for a distance of 82,000 km (51,000 miles).
In the 2.3 L I-4 engine, both oils gave excellent performance as measured by engine cleanliness, oil economy, used-oil properties and engine wear. In the 3.8 1 V-6 engine, both oils gave acceptable main and rod bearing wear protection. In other performance criteria, performance of both oils in the 3.8 L V-6 engine was excellent.